A few concept for specialists we might find in Trier:
A Lame Stone Mason, or Carpenter, who broke his leg during an accident on the cathedral project here in Trier. Master Dombauer introduces him to us, as he can no longer employ the man.
A Failed Master (C&G pg 52) blacksmith, whose Ability Block (Social) meant that no matter how skilled at his craft he was, he could never run his own business successfully. His
young daughter would make an excellent silversmith if the Guilds allowed women, or were willing to overlook her father's failures (appropriate virtues). The wife/mother had been running the business, but is now suffering a prolonged illness that has left the family destitute.
A group of hot-headed young Jews, with no wilderness skills, eager for the chance to live as equals among the covenfolk. The rabbi who joins them is not only more clear sighted, but is an able teacher familiar with the ways of the land, and versed in unexpected lore.
One or more criminals, who were either Branded or lost a hand to justice. My original thought was a small handful, known personally to our mundane friends (Dombauer, David, Amelie, the maid we hire to serve the house in Trier) who has reason to truly believe they are worth a second chance. However, maybe Carolinus met a small band of starving brigands, and somehow won them over to our cause? These would be honest folk led astray, driven by circumstance, not hardened amoral sociopaths. Or at least, not all of them.
Companion concept : a Shapeshifter boy who was raised by wolves is discovered shortly after arriving at the covenant. He's possessed of innate fighting skill, and possibly speaks Animal Ken, but no human language. He adopts the covenant grogs and wishes to join every expedition beyond the borders he's known. He probably has some hidden destiny, or maybe a Death Prophecy.