OP, hopefully the developer in question can refund you.
If not then you'll be forced to take legal action, which anyone obviously wouldn't want to do unless forced to, since it is a tedious process to go through just for something petty compared to the other fraudsters.
It's fair to say that OP has the most reasonable case, unless the dev comes out with his side of the story with fully backed proof. At least you only sent 50% instead of losing everything, op.
I gave him the choice to do that, he chose to once again try to defraud me by claiming work that was not his own.
He did not complete even 10% of the work set out in the contract and i was good enough to let him keep .5 BTC for his "efforts". But he did not want to do that.
So now i want the full 2.2BTC refunded as well as a refund of another client he has scammed.