Simple answer is they defy the national narrative on Covid, on the vaccinations and provide information that helps people prevent getting sick from the infection that is they have caught it but it will never grow in them strong enough to cause symptoms because of the strength of their immune systems. They also provide information from their investigations which they can do as they have access to equipment to test the disease and the vaccines form the makers to see what they are actually made of and what possible side affects may show up.
Being doctors and scientist and many of them with outstanding credentials makes it hard for the powers that be to paint them in a bad light based on their scientific research which is totally opposite of what the government is telling us through mass media. So they have to do pain them in a bad light through associations. In so doing the claim by the government is that because they are not going along to get along then they are causing an insurrection and that makes them terrorist. Sadly many will accept this and never realize it is only the government that us threatening people and using force through coercion to scare people into doing what they want them to do.
Any way AFLD is a somewhat loose organization of doctors and scientist world wide who work together sharing knowledge and information so they can disperse that out to the general public in hopes learns the truth about what is happening in relation to the Covid event from beginning to now.