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.