[ She's not entirely convinced that he is (working for Robin), but rather that he's doing what he has to do to survive and while Scarlett might want to find fault in that, she finds it's not so easy for her to do so. She's done plenty in the name of survival that other people would frown on, but arguably the difference is that Scarlett won't do things that throw innocent people to the wolves. ]

Maybe not. But he still might be the best shot we have at getting out of this alive.

[ Mostly because Scarlett is banking that Will's desperate desire to survive, will be what makes him do whatever he can to get out of here. ]

Just need to make sure that shot doesn't come at the cost of others.