Despite what Nex is saying, most of the clues point overwhelmingly to him. I could tell you that I'm 100% certain I'm not the wolf, either, but as Squee has made it taboo to reveal our roles to each other, I couldn't actually convince you of that. 

The only other person I considered at first was Nat, as s/he's the last one out of the bus and there's nothing written that indicates what order folks traveled in once they were off the bus.