No one here (beside GH staff) can really speculate as to why it was banned. As you mentioned, something about that repository triggered concerns about violations of GitHub’s Terms of Services. Maybe it’s a good time for you to go and read again the GH TOS, Code of Conduct, and EULA documents, maybe the answer is there for you.
As a general rule, repositories get usually banned either because a user reported it due to some obvious violation, or because it triggered some algorithms that inspect GH contents periodically.
Possible causes are (but no limited to): inclusion of Copyrighted material (e.g. eBooks marked as copyrighted); contents included profanity, offensive or pornographic material; files in the repository exceeded the amount of space allowed for a repository (although usually this would simply prevent contents from being actually uploaded).
It’s Summer time, so GH staff is probably less that usual right now and, besides, there are always tons of requests to be processed every day. So I guess that you just need to wait, posting here won’t accelerate your ticket, it might actually slow it down since it will take precious time away from GH staff members. I can assure you that support tickets don’t get lost in the process, they are queued and handled according to the priority they deserve.
I’m confident that your problem will be eventually resolved, and that if it was a misunderstanding your repository will be restored.