I do believe that you'll benefit most from correcting and otherwise educating people rather than suggesting that they should stop speaking. Consider a debate with a Holocaust denier: you begin by listening to what he has to say, then you explain calmly why he is wrong, providing him with mountains of evidence. You cannot educate people by telling them that they are too ignorant to speak; that only reinforces their misconceptions.
It's not for my benefit, I already received a life-saving transplant. My point is, there are many places that people can go to get great educated facts on transplantation and this isn't one of them. You have to go to the people who know best. Your local OPO, http://www.unos.org or http://www.donatelife.net/