If you really want to know who he is he posted his TK-ID in the sales description. But there is actually no mention that he is the one doing the recasting. He could just as well just be a front/reseller of the kits.
But I'm no fan of what he's doing, that's for sure. It's doing nothing to help the legion look better, and it screws over the customers by taking their money that could be better spent on a more accurate kit. But that goes for all of ebay. To be fair, he has the most honest sales description of a recast fx-kit I've ever seen. Doesn't make it right though.