I have his email, tg handles, and IP address (is it okay to make that public)?
We're not law enforcement - his personal information isn't going to help here unfortunately.
I think it would be a bad idea for admins to hand this account back to the previous owner, who voluntarily handed it over to someone else. There was no hack. There may have been some sort of a sketchy deal, or the OP might be lying, they might have been paid (monetarily or otherwise) for all we know. Only a proper escrow could possibly untangle this mess but it's too late for that.
You're right to some extent - the recovery team would not want to be in a situation where someone sold/gave it as collateral for some sort of business and then somehow locked the account after successful agreements, attempting to get it back through the back door; I'm not saying this is the case here, but we've seen situations like that before.
I can't confirm whether the story is true or not, but I also have no reason to doubt it. It will be difficult to persuade the recovery team after reading this thread but it is up to them to decide.