So, you violated their ToS, specifically that you're not allowed to do things that are abusive. Attempting to bruteforce a login is abusive. You admitted that you were in fact doing something against their ToS to them in a ticket. They don't know it's for a university assignment and chasing down your professor to confirm it is an assignment isn't something that's reasonable for you to expect them to do.

You violated their Terms, plain and simple. They don't owe you a second chance or your data.

As a side note, surely a CS major knows they should keep backups of every thing. Better yet, shove your text/code files into git and have backups AND versioning.