Wait, what if the account was sold with the private key that could sign the messages?
If private key was sold together with the account yes its possible to sign a message from an old address and the only way to prove if its sold is "if" the escrow will say anything about the trade and "if" escrow was used. But I don't think account was sold. That loan amount to too small to ruin the account. he could have asked for a higher amount if he plans to scam.
Exactly, if there was a new owner they would already be at a loss because a hero account with a little green trust and private key would cost more than 0.025btc.
Im sure loan will be repaid if account was not hacked.
Scammers will normally move funds straight away and as of now btc is sitting in the same address as it was sent to.
Next time do a little homework and check at the very least 3 things.
1) Check trust feedback.
2) Check if the address they are requesting btc to has been used/posted before.
3) Ask for signed message from an address the user has posted at least 2-3 months ago.
Good luck, hope all goes well and I will follow this thread.
