Pete kinda explains it...Gary did the same he did with Russell at the end of Chapter 1,or with Tad in Chpt. 2,etc.: Started talking lies about Jimmy and successfully attempted to turn them against him...And..Since he "never escapes a notice of anything"(as he says),he got told of what Jimmy was going to do in the Hall,and told Crabblesnitch..
Gary's idiot ball cannon working overtime... ugh... hate this part of the story. Russell only fell for that bs once, he already had good reason to hate Jimmy and he's considered an idiot. Russell might be the smartest guy in the game. Almost everyone else falls for it multiple times. If Gary was credible fine, but it's established incredibly early on that he's not very well liked. Sure they might hate Jimmy more but... geez...
As I've said before, it'd be much better if Gary didn't reveal his true colors until MUCH later, like chapter 5. That things just go against you and you're not really sure who's putting ideas in people's heads because Gary's the one directing you in terms of the best move to 'control'. He can't be so obviously shady but I guess that'd go against the 'dumb majority' like thing he has going for him.
Things I know that no one else does? Eh... I think at this time... very improbable. So I'll resurrect something that people didn't seem to know at the time...
Do the creepy shuffle!
Complete with one sided sound! Ugh... this problem bothered me.https://www.youtube.com/watch?v=NNBi_AWkJLE