Okay, try a different angle on this. Her liege is going to... be consuming some affinity mats, Almys is going to be renting crafting textbooks for her - if they're cheap enough, maybe Almys should just buy them, so that there isn't a record of rentals - and possibly at some point they'll be selling some fine but totally normal-looking weapons. Almys might have to buy 'spellsilver' and come up with an account of that...
Librarians! Librarians are weird and quiet! Or... somebody studying the history of weapons who's a crafter themselves but mainly interested in history...
What if somebody asks her liege about history.
Could her liege just be mute. No because there's such a thing as sign language and somebody might know that sign language.
'Librarian' is good for weird and quiet, and it doesn't get subjected to easy challenges about 'what does this book say' because librarians don't necessarily read the books they organize and protect... Almys thinks you don't have to read a lot to be a librarian, right, you just have to be in charge of a library...
Maybe Almys is overcomplicating this.
Weird crafter who doesn't talk to anybody except Almys! And there's a reason she doesn't talk, but nobody can know it because it's private so fuck off!
...this sounds incredibly suspicious. But maybe that's just because Almys knows the truth. Like. No spy would take an incredibly suspicious role that would prevent them from talking, right? So smart people will realize that her liege is like obviously not a spy.