I think I mostly trust him here. He can only use this to kill the people so powerless that they need his help getting across. I don't see why he would start a fight with the paladin and burn any chance at getting closer to Tobi just to kill someone he could kill at any later opportunity.

I would be pretty surprised if he dropped anyone to die (or into the rainbow for someone else to kill). That said, he might not fight that hard to save someone if they're attacked or hindered by another player.