Lets see another perspective that you might have got his account credentials and sold his account, as he still owes me 0.36 ETH [1400 usd] more than yours.
This is getting ridiculous. I think none of you would sell the account. What is the possibility that Stedsm is Marco and all other accounts that Shasan mentioned? After checking that Stedsm has a years-old loan, don't you think he might have a habit of taking loans with multiple accounts, and those accounts belong to him? If all of those accounts are handled by one person, then all the accounts should get negative feedback and that's it. They don't have to admit that they own all those accounts. If one or two of them were tagged without enough evidence, the account owner should step up and say something.