Crazy guy Gary theory and the other insane people(spoilers)

A lot of people have been talking about the crazy guy that got everyone killed. Some people seem to think this is a plot hole or inconsistency. What I think is that Gary was telling the truth. He came from a hospital for the mentally unstable. While he was a patient there he was properly medicated and believed he was well enough (all things considered). So when the people who were really clinically ill looked up into the sky they became obsessed with making people also "see". Gary had been stabilized and was trying to survive like everybody else. He didn't look at the sky. He put on a blindfold like everybody else and he fled. Fast forward a few weeks and Gary is no longer medicated and still highly schizophrenic and bipolar (two disorders that are fairly highly comorbid). Maybe he's hearing or seeing things again. He's manic. He pulls out drawings of things he used to see (not the actual creatures, just things he sees). In his manic state the voices in his head are overwhelming and tell him to look out the window. He looks and he snaps. I didn't read the book but that's what I assumed happened.