Before you do, consider that we have nothing linking dmf to the guy in the photo other than that we have a single instagram photo of the guy with the tag "dicemasterflash" on it.
That's all.
How's this for a theory:
dmf *isn't* the guy in the photo, but he's watching this thread, sees some innocent guy in New York get incorrectly dox'ed, and thinks "if I start making some token refunds right now, all those idiots will see it as proof that that's me in the photo"...
Crazy, right?
Quoting for emphasis. This is a theory I'm inclined to believe.
If it's not the same person there has to be some connection between those two, right?
So what happens if Mr. Innocent gets inundated by phone calls or gets a police report filed against him or just googles his name one day? I'm not saying it's right or wrong to tie a person to a scam that way, just trying to follow this assumption further.
I wouldn't make threats or do anything stupid, but definitely see about filing a police report if possible or see if you can convince an officer to investigate and bring you along.
Try to file a police report. When they're done rolling their eyes, they'll tell you they don't have jurisdiction or this is a civil matter, if not because they believe it, because they don't have time to deal with a bunch of internet detectives crying over an imaginary currency they've never heard of (from their perspective).
This is basically how I would imagine the exchange to go:
Cop: So you sent him money and he didn't return it?
You: Yeah.
Cop: It's a civil matter, sue him.
You: I don't know who he is.
Cop: I guess you learned a valuable lesson then.