I know how it feels to have your car keyed and I know exactly what I'd have liked to have done to the person responsible...

I didn't even bother going to the police when my car was keyed as they wouldn't have done anything. The difference here though is that you know who the culprit is... Talk to the supervisor and see if they'd be willing to go on record to the police.

Failing that is there no way you can catch him in the act now you know it's him? I guess that risks further damage though