I shouldn't confirm or deny suspicions since it spoils the surprise, but hey! Yes, you're right. I reeeeaaally need to figure out better why he did it, though it was basically because he thought his family was threatened and he'd be better on his own. I don't think why he faked his death is going to be that important in terms of plot (this is not as well planned out as, say, Loyalty) but Bran is certainly going to want to shake it out of him!