This is one of the confusions that the readership sometimes has about these sorts of stories. The characters don’t get to read the comic books that you do–they only get to experience whatever portion of the story that they’re in. And even in a super hero world, the thought that somebody is acting surly, so they must have had their brain switched is pretty far-fetched. Now think about it. If your wife suddenly started acting a little bit different, a little bit peculiar, you wouldn’t immediately think, “She must have been replaced by a double!” unless you’re a very disturbed individual. No, you’d expect that this was something that she was going through and needed you to be supportive about. That’s one of the reasons that stories like this one can be difficult to pull off, the reader knows something that the majority of the characters don’t, and so can get frustrated metaphorically yelling at them to notice something that’s incredible unobvious in the first place.