The school doesn't even need to do that to effectively squash suspected behavior in the short term.
Maybe they can't dole out a substantive punishment, but when I was growing up they absolutely would lean on kids for even being suspected of doing something, or even if they hadn't done it yet, but the administration could see it coming. Sure they might of wasted some time on kids that truly weren't up to anything, but there generally weren't actual punishments of consequence on those cases. I'm pretty sure that a few things were prevented entirely, just by the kids being told that the administration sees it coming.
So they should have at least been able to effectively suppress the student body behavior while they worked out the truth.
Nah, AI code gen bugs are weird. As a person used to doing human review even from wildly incompetent people, AI messes up things that my mind never even thought needed to be double checked.