He still isn't sure he believes getting out of here is possible. He isn't even sure if he thinks it's more or less likely as his suspicious about how and why seem confirmed.

But he isn't sure he believes it's impossible, either, and there being an end point is a thing he's going to hang onto as a means of coping.

"Oh, did he decide to be helpful?" He's pretty sure if that's the case, this is going to be a whole new interesting experience. But only pretty sure. That man is... infuriating and in part because he is... He isn't erratic, he's just unpredictable (make things worse or defy expectations or-) for Steve, and Steve hates that.