I had the same problem which I used my cousin as the middleman, but before I even revealed to the guy who the middleman was, I made a secret password...
The items were stolen from a rarely used method because the type of hack that they have is very private, meaning either that person created it for...
The thing is it was not a scam nor was it even a phishing attempt. It was stolen in a different method that was completely out of my cousin's hands.
I refuse to have my cousin stop with the steam support. I will have him keep spamming their asses till they do something because if they don't...
He is now trade banned, but Valve still hasn't done anything to help my cousin out. They keep giving out these bot replies that we somehow have broke...
I have also dealt with this trader and got my items hacked, but it was the "middleman" that he requested from me, which was my cousin that was hacked...
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