He's about to say something to defend himself, or at least make the other stop assuming things about him, but when he mentions Scott, everything else flies right out of his mind. "Wait. Scott's here? Where is he?"

Stiles and Lydia might not trust him, and honestly, Scott might not either - but the latter of the three might be easier to deal with as far as collecting information goes.

He doesn't say anything about being told to stay away from them. And he isn't going to until he gets some answers.