Do not pass go, do not collect $200.
If the account owes someone money via a loan then you should pay the loan regardless of if the account was "sold". If you don't pay your debt to the lenders satisfaction then you will likely get negative trust.
If you really purchased this account then you should have checked for outstanding loans prior to paying for it.
The lender has no way to know your IP address.
Edit: why don't you post the lending thread/post? From what it looks like, the account took out a loan from magic8ball then a short time later he posted that the principal was returned and that the account was returned to the owner.
QuickSeller how do we know this guy really bought this account recently?
How do we know he's not just saying that to act all innocent, pretending he has no knowledge of previous wrong doings on this account?
It'd be pretty easy to have loads of negative trust & then one day say 'I have just bought this account, how do I remove the negative trust, it's nothing to do with me'.
I'm cynical but happy to be proven wrong & the OP to prove his innocence.