If it turns out that the girl was in cahoots with bullies from the start and was just doing all this to trick the MC, I won't trust anything from the Author again.
It would also mean that she was taking backshots of (feigned) contrition for the sake of elaborate bullying.
Honestly, it'd be more laudable than being the one giving those backshots of "revenge"-- but I don't think you can manage a heel turn after allowing your victim to accumulate so much "this you?" material.