Why so certain about Bredon? I didn't see any hint that he was an Amyr, other than the rumor about him engaging in some "pagan ritual" outside of town.

He plays the game with Kvothe, catches him up on court gossip, and teaches him about local customs. Does Denna ever indicate some tie to Bredon?

I suppose the biggest hint would be his instruction to Kvothe in the stones game (I forget the name). Also, didn't the Cthae say that the closest he would get to the Amyr was in the Maer's court, not the Maer himself? If so, Bredon was in the Maer's court and spent the most time with Kvothe, so it makes sense.

I definitely think there's an Amyr at the University, though who it is in anyone's guess. It might be puppet, for all I know. Though I would suspect Kilvin or Arryl just the same.