I emphasized that his best bet would be to find another dr. first, so that he could get an objective professional involved.

I decided that it is not my job to decide what is true or not, but rather to just be a supportive friend. I think the way I can be most supportive is to help him find a really good doctor so that he has a professional helping him figure this all out. If he does decide to file a complaint, I will talk to whomever and share my concerns.