The mere existence of a black market for human organs should raise major fucking alarm bells. Organ transplants aren't something that you can get done in a dodgy back alley clinic. You require modern hospitals with highly trained surgeons and a team of staff. One would imagine that the hospital would have some questions if you rocked up for a liver transplant with your donor liver in an Esky. So... how do the black market organs get into their patients? The only conclusion would be that some (or all) hospitals are in on the practice and that (for a fee) they can "acquire" an organ for you without needing to wait for the right donor. The other possibility is that the harvested organs are not typically for transplant, and are instead destined for the culinary or ritual market. Pretty sure jews have been harvesting the organs of gentiles since well before organ transplants were a thing.