You ever been on r/wallstreetbets discussion board at the top of their sub? They are literally planning manipulation trades to push stocks up or down. The mods say it's a bankable offense as it's an SEC violation but they do it anyways.
If you believe the hype then it's not a short squeeze so much as they are just buying. Buy Buy buy at higher prices. I think the setup is more that at some point the big institutions will push it down stopping them all out and creating another but fear type market but I think it has a long way to go yet.
I don't know. I would surmise that they could if they were coordinated (e.g., at 11:00 a.m., let buy this stock). I would think such coordination would be akin to herding cats.