River just posted in another game, I think...
Oops!
For some reason, I feel he could know Arcata. Not entirely sure why, but they do both have a connection to magic they don't understand. And, he could help her learn the peace of mind to control her power. In fact, that could be how they know each other. Perhaps the mages who held her tried to get her to learn discipline by employing a Monk, and that monk was Nicolo, who, at the time, was taking every chance he could to get out of the Monastery. The lessons may not have stuck, but it's a thought. Or something like that.
Sorry, man! I missed this completely!
It's not a bad idea, and more connections is a great idea. The only potential issue is that I think the Guild sages who had Arcata were trying to keep her something of a secret? So there would have had to have been a reason they trusted you with that secret.