im sure if he didnt give them access anyway they would take legal action or some bullstuff
What legal action could they take? They're a school. They can't press criminal charges because they're not a crime fighting agency and they can't file a class action lawsuit because they're not a minor that he loveually harassed. They could
try to suspend or expel him, but they likely have no grounds to do that without completing an investigation that was thorough and condemning. They could try to claim that he isn't complying with the investigation, but that would easily be argued against as it's an unreasonable expectation of compliance for someone to open up their private accounts.