Why would knowing the doctor have anything to do with the hair that grew and then him losing it. That is not a doctor issue, so please don't say if it was done by a "TOP" doc, it would be different...(except only putting him on finasteride, minox). If the results were poor yield (or taken from the wrong donor area) then I agree.
We all have biological differences, the docs job is to get it into his head and grow. After that, it is how he responds to hormones (DHT, etc, and other existing medical issues).
With that said, the part that scares the crap out of me, and should you guys, is why the heck the transplanted hair was permanently lost!