(That depends. Make an argument based on the lab total necessary to invent the spell and how much you'd accumulated, and time this to when Laetitia comes to get Alexei. Willhelm reported Fieltarn missing after about a week of waiting for him. All that info should be enough to make a calculation and/or argument for having the spell.)
((Spell's level is 25, lab total is 42, would have 17 points finished on it from the first season of Fall 1221, he'd have 8 points left to finish the spell.))
"That would only be possible if this were an official Quaesitorial investigation. Fieltarn is suspected of no crimes to my knowledge, but merely missing and possibly in trouble. You would be the first I'd come to when I have the need for, and the ability to designate, a Hoplite.
"I only have one shield grog, of course, and he... doesn't exactly take orders from anyone outside House Tremere. He is loyal to me because House Tremere has requested that he do so. I am certain that even the friendship he and I share would be inconsequential should House Tremere require it of him." She frowns.
She looks a bit embarrassed. "Ahem... I thank you for the consideration, but a quaesitor cum auctoritate does not forfeit immunity upon entering a magus' sanctum. That's.... that is the law, regardless whether I agree with it." The look on her face makes it clear that she does not agree with it, and she shifts her weight uncomfortably. "I will wait outside."
Alexei nods in understanding for both her statements. "Best to be safe, I know. A moment then." he enters the sanctum and begins gathering some affects into a bag. "Helmut! Get your things, then send a message to Michelle and Brionne, tell Michelle to gather two of the new Grogs and that Brionne shall be my shield. We'll need a hand cart as well, get some food and other supplies." Helmut snaps to attention and begins marking off the things to do on his fingers before leaving, not without a longing last look at Latitia.
Alexei is out of his sanctum a few minutes later, it seems he is usually ready to travel and a ring with an amber stone is now on his ring finger of the left hand. He has his staff with him, a heavy cloak and a sling bag.
"M'lady, if you and your grogs will allow, I do have some subtle enchantments ((for as blunt as Alexei is, his magic is barely noticed)) I can provide magical armour as well as make it stronger and lighter. If your concerned for your own safety, a suit of chain that feels only as heavy as winter clothes can be provided for you to wear. As my pater would say 'Trust your shield grog, but Ward yourself'. I wear it all the time myself. I can also provide enhancements to your shield grog that he will likely appreciate. Shall I conjure a suit for you and let you feel its weight?"
"I wouldn't know the first thing about wearing armour," Laetitia laughs. "But I suppose it is worth a try. Shall I suppress my Parma, or do you think you can... penetrate?"
(("What is Penetration and how do I get some?" --Best AM quote of all time.))
After endless banter and double entendre Alexei, Laetitia and their attendants arrive, dragging Wilhelm along with them. (Make whatever preparations you feel are necessary. Spellcasting is not under stressful conditions, so if you can cast a spell automatically if your CS is sufficiently high.)
The temple seems rather ordinary, and is in an obviously ruined state. It is winter time, but the weather is not too cold for the time of year.
((This is what would have been said in their banter I suppose))
Alexei has a wry smirk on his face at the banter from Latitia. "Well m'lady...Penetration is a specialty that I often excel at...Flambeau's contribution to Bonisagus's craft and all. I contribute as often as I can of course." he brings up his staff. "However, let us keep this...professional. Allow me to conjure it and you can slip it on."
((Casting Silvery Scales of the Knight, Hauberk of Supreme Lightness, and Hardness of Adamantine
The casting rolls can't really be failed due to the Aura and it shouldn't be stress, but he needs to make a stress roll for the Finnesse to craft the armour:
Int 2 + Finesse (Crafting things with Magic) 4, needs at least a 9 for average quality armour:
1d10+6 → [1,6] = (7) (exploder die!)
invisiblecastle.com/roller/view/3338322/
Exploder:
1d10 → [8] = (8*2) + 6 Total for Finesse roll 22
invisiblecastle.com/roller/view/3338323/
I'll leave any actual game affect embellishments for what the armour quality provides to the GM, it will only last another few hours anyway. Since he's concerned about making this armour comfortable for someone who doesn't wear it normally, maybe the Load is reduced? With the Hauberk of Supreme Lightness on it, the Load would be 2))
Alexei stares into the space between he and Latitia for several seconds before a gorgeous and glimmering suit of fine chainmail slowly takes form, hung on the end of his staff. It looks to be tailor made for the smaller form of the female body, but lacks none of the protection. A smell of fine perfume seems to eminate as he continues to concentrate, but neither speaks nor gestures. The perfume smell changes to fresh cut pine and finally pleasant incense before he looks up, seemingly finished with the armour.
"Ah...excellent, I believe I assessed your form and shape properly for this. Please try it on." he closes his sanctum door and locks it and then heads to the other door so she may have privacy, carefully draping the suit over the chair. "I believe it shall cling to you lovingly."
"Oh... thank you, Alexei. I... ummm...." She turns around and calls out, "Elain! I need your help please!" She'll have Elain help her put on the chainmail, and then cast Bitter Taste of Betrayal on herself. A burden of 2 gives her an encumbrance of 1. She has +1 Stam and a 3 Bronze Cord score, so her Soak will be whatever the armour's Protection is, +4.
((the Soak total of the armour with Hardness of Adamantine is +11))
Alexei calls from outside the chamber as she is dressing. "I often follow it with a casting of Doublet of Impenetrable Silk (+3 Soak) and can further add to it with Gift of the Bear's Fortitude. That won't do you much good of course as it is a personal spell. But between the armour and doublet, you should be well protected and only slightly hampered. If the armour is too uncomfortable m'lady at least let me cast the Doublet upon your clothes, should you not know the spell of course."
She looks a little shifty as she dissembles. "Ah yes, well, I can't quite see the point of Muto. It strikes me as a singularly useless Art," she declares. "I will try wearing this armour. It does fit rather nicely, after all. Even if it is quite unseemly for a woman to be dressed as such. But-- as they say, Safety First!"
[spells cast on Warrior Grogs:
Hardness of Adamantine, Hauberk of Supreme Lightness, Doublet of Impenetrabe Silk
Spells cast on servant Grogs: Doublet of Impenetrabe Silk
Spells cast on Latitia (if allowed): Silvery Scales of the Knight, Hardness of Adamantine, Hauberk of Supreme Lightness, Doublet of Impenetrable Silk
Spells cast on Alexei: Silvery Scales of the Knight, Hardness of Adamantine, Hauberk of Supreme Lightness, Doublet of Impenetrabe Silk, Gift of the Bear's Fortitude]
Alexei took his time at the outset of the journey to heavily fortify the gear of all those who were attending. No doubt Latitia's remark that Fieltarn likely met with danger increased his caution.
((For Latitia's reference, all the spells he casts are without gestures or words, in fact it seems that he mainly makes a show of personally inspecting their gear and at some point a pleasant smell that varies from person to person emanates, and strangely all the recipients seem to be in a better mood afterwards, as if there was some pleasant side affect to his magic))
Once at the temple he turned to one of the two Grogs that Michelle had brought. "You shall stay here, guard the luggage and the servants. At the first sign of trouble call out to us. Arm the servants, I brought some extra spears. Caution and prudence are more important than bravado right now, understood? Servants, do what you can to to prepare camp, but do not stray from the guard's sight, and light no fire yet. We may be sleeping outside or in, depending on what we find."
Alexei goes to the cart and pulls out a magnificent shield, embossed with arcane symbols and is expertly crafted. He walks to Latitia's shield grog. "If you wish you may use this to protect your mistress, it is an excellent shield, crafted by a Verditian smith. It will not fail you." ((This is a shield enhanced by the Verditian Mystery, it adds an additional +5 to Defense)) "I will not presume to command you nor ask you away from your charge, but I may cast further spells on you to protect her better or to enhance your skills. Do not be surprised by this, I'm sure you have some experience with magic in the field, yes?"
From the cart Alexei also pulls a pair of equally magnificent sword and hands one to the deformed Brionne who dutifully and reverently swaps it with his own, giving his sword to one of the servants. Alexei and Brionne exchange a brief nod; they have campaigned together so long nothing else needs to be said. ((the sword adds +4 to attack scores against men or animals)). He gives the other sword to his sergeant Michelle la Rouge, who adds it to his belt. Finally he makes one more trip to the cart and takes out a small but elegantly crafted leather pouch. It's been treated with oils to keep its contents dry and is decorated with entwined snakes. He brings this to Latitia.
"The same Verditius wove these bandages, even if you have no skill in chirurgy, just wrapping them on a wound will be helpful. If you would hold these m'lady and keep them safe until needed." ((bandages add +4 to any recovery roll)) he says, his fingers brushing her hands as he gives her the pouch.
"Now then!" he adds as he addresses the group. "Keep your eye peeled, cry out if you see danger. M'Lady, if we can avoid crossing a regio, let us do that until we are well prepared." he says as he takes a spear head from a pouch at his belt. He brings it to the end of his staff and there is a slight ping of wood striking metal, when he lets go of the spearhead it is afixed firmly to his staff. "Michelle, find a suitable entrance to the temple."
[Gear in cart:
Winter clothes and bedrolls, several days of food, dry firewood and tinder and flint, extra weapons (6 shortspears), 6 wooden shields 3 shortbows and 2 score arrow), lanterns and oil (3 lanterns), rope (20 yards)
I was going to bring some iron spikes, a silver mirror and a 10 foot pole, but I figure Alexei can conjure those if necessary 
]
Wilhelm is going to dress warmly, in the manner of a man who will be spending a week in the woods in the dead of winter. He has a bedroll and something to make a makeshift tent or lean-to with, as well as a handful of snares to set for catching rabbits or other small game for the week that he expects to be waiting for the magi. His unstrung bow and fully-stocked quiver are slung across his back as well.
Does Wilhelm count as a "Warrior Grog"?
As the...expedition gathers at the covenant, Wilhelm looks more and more surprised. He had expected a handful of people, at most (the two magi and their shield grogs, with maybe a couple more soldier-types, as well)...not this...parade. He will finally just shake his head silently.
[color=green]"Do you want me to go ahead to be sure the trail is clear, or....?" he asks the magi.
((To be honest, I'm not even sure who Wilhelm is, I couldn't find him in the Grogs thread, I'm going to be very embarassed to find out he's a custo or something 
. Simply put, if he wears metal armour, Alexei will offer to lighten it to 2 load for a full suit or 1 load for a half suit, and enhance the soak of it by +2, if he's wearing no armour and wants some, Alexei will offer a suit of full chain that lasts until sunset with a soak of +11 and Load of 2. Either way he'll get a +3 soak from Alexei casting the Doublet on him.
As for numbers, I had it figured like this: Alexei, Latitia, Michelle, Brionne, a shield grog for Latitia (I thought Whilhelm might have been her shield grog), two more warrior grogs, 3 or 4 servants and a handcart (so about 10 people). Wilhelm can be the expert. Alexei is generous, if Wilhelm or any servants ask for armour he'll provide it. Feel free to have Wilhelm grab a spear and shield and/or bow.))
Alexei purses his lips as he regards Wilhelm, trying to remember if he's travelled or worked with the man before. Looking at his clothes and manner Wilhelms seems to be a bit of an outdoorsman. "Yes." he agrees with a nod. "You're armed then?" he gestures to the weapons brought in the cart (Brionne's sword is there now as well). "Don't go too far ahead if you please and signal us of any danger."
That's because he's a Companion. Has his own thread here, and his own page on Obsidian Portal.
He normally wears Heavy Leather Armor. But if he's offered chain mail that's lighter than what he's wearing now, he will accept...especially if it's the same kind that Alexei's already created for Laetitia and Wilhelm, with the maga's permission, checks it out to be sure it's not too clunky or clanky.
He will remove his leather armor (which I'm assuming is his top layer) and put the chain mail on over his clothes, placing his own armour in the cart.
I don't believe Alexei has worked with Wilhelm before (Wilhelm was in the "Remains Of Those Who Came Before" and the "All The Leaves Are Brown" threads before this one).
Wilhelm reaches up to touch his bow with one hand and places his other on his knife. [color=green]"I am armed enough, magus," he says. (As an aside, once he realizes that Alexei is speaking with a German accent, he will speak in his native German as well – he speaks no Latin, and his French is a meager 2).
He will travel about 50 to 100 paces ahead of the main party, keeping his eyes and ears open for anything out of the ordinary. Visual spot check: Per 2 + Awareness (in the forest) 4 + Keen Vision 3 + Ways of the Forest bonus 3 + die roll of 1 (followed by die roll of 10, for 20) = 32. (Hey, that ant has acne!). Hearing spot check: Per 2 + Awareness (in the forest) 4 + Sharp Ears 3 + Ways of the Forest bonus 3 + die roll of 0 (not a botch, though) = 12.
As I indicated earlier, travel to the Ruin was pretty easy. It's just across the river from Autun, so it's pretty civilized, with the previous exception of the spectral wolves. Close visual inspection of the temple and environs doesn't reveal anything out of the ordinary.
Laetitia's second sight sees something that looks like a tent flap, closed up.
"Seems like the entrance is here," she points out. She motions for Glaukopis to land on her shoulder, and then she lifts the flap with one hand, and extends her other out behind her to lead everyone in. "Everyone please hold on to each others' hands until we are through the boundary."
Laetitia guides everyone past the point, but they do not traverse the boundary.
As in, she was not able to lift the flap?
[color=green]"I will wait here for your return," Wilhelm says as he starts to unload his things and prepares to set up camp. Unless he's able to squat in one of the cabins that I suddenly seem to remember being here in sight of the old temple.
Yeah, let's go with that.