Stop moving the goal posts. She was punished for having been victimized. By the time she was punished, they knew she was the victim. They knew she was the victim, they had evidence that she was the victim, and they punished her anyway. The problem here is the egregious way the school has handled the entire issue, not the outstanding criminal investigation into the boy.

There. They didn’t have any proof prior to the fight.

You do need conclusive proof of the accused’s guilt to punish the accused. You do not need any evidence whatsoever to start protecting the accuser from the accused. The school could and should have either kept her off the bus, or provided adequate supervision of the two. They failed to properly supervise the two, directly leading to the fight. They forced harasser and accuser together without supervision. The fight was foreseeable; the school is responsible for it.

Second. How do you get those photos and videos (assuming it wasn’t a bus security camera which wouldn’t be able to make out the photos anyway)? You need a warrant to unlock student’s phones.

It was, indeed, a bus security camera. And you don’t need a warrant when the photographer gives you their photo. The school was in possession of this evidence prior to the disciplinary hearing where they unjustly punished her. They had this evidence, yet they punished the victim anyway.