I also traded with this guy. I sold him 10m, but he still has not paid me and its been 3 days. He says he sent the bitcoin, but he can't give me a transaction ID and the transaction doesn't even show up as started. I can't say 100% that he is a scammer, but it certainly seems that way at this point. He does also have an account named "Phoni" because thats who he asked me to give the gold to. Here is proof.
http://prntscr.com/g4nye5