I wouldn't until i put down that little rebellion. They might be infiltrators. And Nuncio wasn't scared of Zevran, he was scared of confronting the whole Dalish clan, which given his numbers, was wise. I didn't see anything, indicating that Zevran was a major threat to the organization.
First off, Zevran wasn't scared of the Dalish clan. I have no idea where you got that from. They knew right where he was and even one of the NPCs tells you as such. He wasn't scared of them, he was making sure that they didn't get hurt.
Little rebellion? Cute. Nuncio wasn't scared of him? That's a rather deluded statement, don't you think? When was the last time you even played the games?
And I guess the entire dialogue when the Crows are coming after Zevran about him "taking them out one by one" just fell out of your head. It must have been a long time since you've played DA2 at all.
What if Zevran was dead? What if he didn't start a civil war within the Crows? How would go think a group like the Crows goes about recruiting, outside of little boys from brothels? I'm trying to have a friendly discussion here.