The area had been settled by the time the ancient city of Akhetaten was rediscovered. I haven't been able to find out exactly when the area was settled, but it is not impossible it was settled already in the C13th.
So it is not so strange to have a modern word for the place already existing when they first realized that a lost city was buried under the sand, and partly under more modern villages.
All the sources I have been able to find on the Internet claim that the name Amarna was derived from the Beni Arma tribe who lived there, but I don't know how reliable that information is.
Amarna - Ancient History Encyclopedia
In the present day, the site is a wide, barren, expanse of ruined foundations which is being preserved and excavated by The Amarna Project. Unlike the ruins of Thebes or the village of Deir el-Medina, there is little left of Akhetaten for a visitor to admire.
So no, it was never resettled. It was renamed, supposedly, for the people who lived near the ancient location in 1887. Although on Google earth the nearest city appears to be Dayr Mawas, located 2.3 miles from the dig site, and across the Nile, while it appears to be in the jurisdiction of Tall Bani Umran. It was supposedly named for a nomadic tribe in the area at the time of its discovery, which would not apply to the 13C CE.
Nearest city is on the other side of the Nile from Amarna, but there are villages on the same side as Amarna at the edge of the river.
Regional Setting - Once You Are There - Accessing the Site - Amarna Project
Four villages lies along the edge of the Amarna plain, adjacent to the river and the modern fields. They are, from north to south, Et-Till Beni Amran (or Et-Till), El-Hagg Qandil, El-Amariya and El-Hawata esh-Sharqiya (or El-Hawata).
Also, Amarna was never really a "lost city". That there were ruined buildings there was well known to the locals, even if they didn't know it was the remains of Akhetaten.
Anyway, the place and its ruins was well-known before they started doing any actual archaeological excavations there, so that it had a name before the ruins were identified as the remains of Akhetaten is pretty natural.
But I do admit that it is not at all clear that the place had the same name back in the 13th century as in the 18th century, but not all that implausible either.
Given that the dig site history explicitly states it was named after a nomadic tribe that was in the area at the time of its discovery in 1887, I do find the idea that it had the same name in he 13th century extremely improbable. It would be like finding out there was a Native American tribe called Trenton right in the area associated with the modern day capital of New Jersey.
It was discovered and named a bit earlier than that - even if you don't count the locals, and only include Europeans. Napoleon's army passed through that area in 1798 when they were in Egypt and paused to create a map of parts of the ruined city. http://www.amarna3d.com/amarna-discovery-timeline/
But now we are getting into details and very much off-topic.
I concede your main point though - that if the area was named in the 19th century after a local tribe that lived there, it is unlikely that it carried the same name back in the 13th century - but on the other hand we don't really know how long that tribe had lived in the area. According to this https://www.arch.cam.ac.uk/research/projects/current-projects/amarna-egyptian-archaeological-heritage/amarna-site-management the district was associated with the name Amarna (after the tribe) at least as far back as 1737.
But even so, we still don't know what the area was actually called back in 13th century. It is much more likely that it was called Amarna (or something similar) at the time than that it was called Akhetaten, but neither seems very likely. So the options appear to be:
Call the place Amarna
Make up some fictional name
Do some serious research in some dusty old archives to find out what the area actually was called in the 13th century.
Of those three options, calling it Amarna seems the least bad one - unless one enjoys spending lots of time in old archives.
Or leave it out entirely- the history of Akhetaten had been intentionally erased by the Egyptians over two millenia prior, and while there may have been known to have been ruins there durring the 13th century CE, the story of the place was not necesarilly a part of the 13th century cosmology, and doesn't need to exist in Mythic Europe. After all Sumerian culture seems largely ignored and would have been more familiar to the people of the 13th century (primarilly as it elates to biblical events) than Akhetaten/Amarna.
I don't have "Egyptology : The Missing Millennium" in front of me now, because the Australian interlibrary loan systems are not working properly at the moment, but I'd flag the author, who is Egyptian, makes excellent points about how having Egyptology start when Europeans turn up is a sort of deliberate ignoring of the Egyptians themselves. I flag them because I feel they are strongly relevant to your argument that things are unknown and don't exist in Mythic Europe because you, a modern western person, believe it so. In saying this i know I am disagreeing with your expressed point that you know Egyptian religion and history because your son was "called to Horus". I suggest we are using the word "know" in two different paradigms.
We took modern versions of medieval period texts in Arabic as our sources. We quoted the key modern interpretation of those sources in the author's intro.
Again, and we seem to do this regularly Silveroak, we get to the point where I've done the best I can with period sources, and you're telling me it's not good enough because you or a family member has a link to a living religious tradition in which you have supernatural sources.
That's fine, as a faith position, but it's not a standard we can work in as a product writing team. You need a sort of "show bible" and a peer reviewed external source makes that so much easier that even if you don't have one, the independent researches of the authors tend to create one by default. It simply can't be in one authors head, even if that authors a specialist in the field, because then the team is centred on one person and they become a fragile point in the process.
Unfortunately the sources I have are all written in the modern day, as I do not read ancient Egyptian nor Arabic. On the other hand I have sited sources, which you have not. My point regarding Akhetaten is not that it didn't exist because Europeans hadn't discovered it, but rather that nobody knew its history in the 13century CE. If we are talking about a roleplaying game set in ancient Egypt it would be one thing, for it certainly did exist in the real world, but then again so did dinosaurs which are hardly a thing in Mythic Europe. So did Neaderthal man, which is hardly a thing in mythic Europe. This whole attitude you have that somehow I have a colonial attitude about it while you do not when we are both modern men, of apparent celtic ancestry based on your surname, whose life experiences are in the modern day. If you have some 13 century text stating the history of the site which refers to it as Amarna then please say so and site this source instead of saying you did the best you could with medieval texts. Your modern version of a medieval Arabic text is just as modern as my sources, and you don't in fact make arguments on this point from it, you simply resort to ad hominem about my supposed revelatory experiences which I never claimed- yes I stated that my son was called to Horus, and that is why I have been researching Egyptology for and with him for the past six years- it is not a claim to special knowledge, and if such a special knowledge existed it would be his, not mine, and related to Horus, not the whole of Egypt. Once again your research turned up short and so your arguments become personal rather than academic.
The arabs would have named the place. What name they would have given it? I don't know, but they always sought to give places names, both to use as landmarks, and to assert their dominion over them. Whatever name the locals called it before the area was conquered by the arabs, they likely either translated it to arabic, or changed it completely.
It's far more likely to have an arabic sounding name. As far as whether it's called Amarna or not, it's not unthinkable that two or more places are named the same, or similarly. The extent of the muslim conquests since the 7th Century have been so vast, that it shouldn't surprise anyone that a single name might be used for more than one place.
Except, of course, for the fact that there is a town less than 2 miles away with a different name that was given to it by the Arabs. So unless the Arabs went around randomly renaming every single hill, I would expect they would have left it with the name of the town, Tall Bani Umran. However ultimately the question is about the survival of the legend rather than the incidental name of the place, considering that during the 13th century BCE the Egyptians made a concerted and apparently successful effort to wipe out any record of the place what is the probability that 13 century Arabs knew and believed the story of the place, and if they had done so then why did Europeans, who raided Muslim libraries extensively during the crusades, not find anything out about it until the 19th century when they dug the locations up?
While the ancient Egyptians made a concerted effort to wipe the record of the place, there are two elements that i think you're overlooking:
While the legend might not be known to mundanes, there might be lingering talk about the place being cursed, or haunted, most likely spread to avoid a new city being raised there.
The Faerie, the Magical, and the Infernal, would have no reason to keep it hidden. Some of them might actively try to spread the story, especially when we're talking about the Infernal. A story about how the Divine has fallen? Sure, these things might only be known among the Magical societies in the area.
You are intermingling the realities here.
My point is that the event shares the attribute with the existence of dinosaurs that it was unknown to real world Europeans, whose beliefs are supposedly the foundation of the game, and not being known to them does not need to exist in the Ars Magica universe. How knowledge might propagate differently in the game universe does not influence what was or was not known in the real world.
I think you're reading it wrong. It's not whether an event is known or unknown to real world Europeans. It's whether the event happened.
Real World Europeans had no idea about a lot of things that exist within the Ars Magica universe, and yet those things are a part of the game. Sure, many of them are mysteries even in game, but they are a part of the game nonetheless.
The central conceit of AM is that it is a world based on how Medieval People saw the world. It has been acknowledged at various times to be a failed conceit, but it is the core of the book. It is why Lands of the Nile is committed to a world that began after the Egyptain Empire was established, and tries to explain the monuments in that context.
MY argument is that because, like dinosaurs, the events refered to at Akhetaten were not known it is not necessary by that conceit for them to have occured. The same way the wars between the sea people and the phoenicians are not part of Ars Magica history since they were not known to te Medieval peoples.
Europeans may not have known about a lot of things in the ars magica game, but they had at least heard rumors, or known people that had heard about them, or had some belief in their existance. Also I stated that it was not necessary for these events to have happened in the Ars Magica universe, not that they could not have happened- just about anything can be in ME.
My favorite view is that the "true" spirits of natural things are Magical. As the Magic Aura increases, the place gets more attuned to its Magic spirit-of-place, and in addition more and more aspects of the place get connected to their own spirit (so within the aura you get the river-spirit, tree-spirit, and so on). This is in addition to the magical aura spawning Magical creatures, which aren't spirits.
When the Magical aura dwindles or is replaced by some other Realm, the spirits lose their connection to the mundane Realm, and generally remain in timeless existence in the Magic Realm. Spirits of other Realms can then manifest in the mundane world, but generally these have nothing to do with the Magic spirits and are thus not strictly the spirits "of" the thing. Faeries take-over from Magic, siphoning Magical energy from the Magical spirits, so at least may still have some connection to the natural-thing (the connection being that they are usurping its true spirit...). Divine spirits tend to cultivate or command the environment, but not to be the spirits of things. And similarly for Infernal spirits.
So the way I see the different spirits interacting is that the faerie spirits of a thing generally don't exist until they usurp the Magic spirit, taking on its role. And the Divine spirits are more in-charge of that aspect of the world, rather than spiris of it, and are only appointed to that role when the Divine aura covers it. The Infernal spirits generally aren't bothered with all of this at all, content to manifest as demons rather than worrying over a natural aspect of the world. And through all this, for every natural thing there is a Magicl spirit in the Magic Realm, but it is an eternal being outside the flow of time and only gets connected to the time-stream if its connection to the mundane world gets made, so that its Presence extends over the mundane natural thing.
(A slight exception to all of this is human spirits - which after their death may travel to the Divine, Faerie, or Infernal realm rather than Magic, but otherwise are much like the Magical spirits above: having an eternal, time-less existence at an outer Realm, but manifesting their Presence over the mundane object (the human body) while it is alive.)