It's been pretty common for those illegal, unofficial, unauthorized, non-licensed vendors to scour through and rip off a concept or tweak found in these and other forums. They've even attempted to ask people to provide vector graphics files, probably so they can make it as sharp and as official-looking as possible to fool unsuspecting fans and consumers.
Also, I'm sure they've been infringing on many NBA/NFL/NHL/MLB logos for profit, not just your tribute design. It's like whack-a-mole; one gets shut down, and another one pops up. You can keep reporting them, but they ripped you off because they thought it looked cool and they could probably make a few bucks off of it. Do you think it is an actual Nike jersey? I doubt it. It's all photoshopped and they will make them if people order it, which is why even though NBA authentic or even replica/swingman jerseys are getting more expensive by the year, it seems, one should not pay these other crooks your hard-earned money in case you get scammed and don't even get a jersey in the mail.