You already know the answers people are afraid to ask for.
How much it actually cost. Whether the pain was as bad as expected. What you told your mother. Whether you would do it again. These are the questions that decide whether somebody goes through with it, and they are the questions nobody wants to put to a surgeon.
The most common complaint from transplant programs about public donor campaigns is not that they produce too few enquiries. It is that the people who come forward arrive unprepared — they have not been told what donation involves, what it costs, that they can stop at any point, or that not being a match for the person they hoped to help stopped being a dead end years ago.
A twenty-minute conversation with somebody who has been through it fixes most of that, and no amount of well-written web copy substitutes for it.
What this is not: you are not giving medical advice, not assessing whether anybody would make a suitable donor, and not being paid — for your time or for anything connected to a donation. You are telling somebody what it was like. Their transplant center does the rest, and that is their job rather than yours.