How would he be putting his neck on the line? If XCrowd doesn't deliver, he just returns the money.  What's the risk?

Anyway, I don't really see the need for Escrow, if you don't need the order money to fund production why not just let people buy when they're ready to ship? Why bother with the whole pre-fund escrow thing at all?

The only reason I can think of is to lock in sales in the event the difficulty goes insane and the units would no longer be profitable.   If you're units are going to be priced at a rate that will make any money for anyone when they're actually released, you shouldn't any kind of long-term escrow.