The problem your son got is indeed horrifying. Are you able to get compensation from a court? If not, then it's understandable why you're crowdfunding.
Vaccine injury is an issue that has been ignored for years, maybe even decades. The mainstream media doesn't want to talk about it, but should you talk about it, you're being ill-defined as an "anti-vaxxer". So here it goes, the first logical fallacy that will be used against you is a strawman fallacy. They then move on to ad hominem. If these arguments fail, they move on to rationalization and even saying things that are not true or even unscientific. Example for such assumption: "There is a safe level of mercury". What the scientific studies however say about mercury is: "There is no safe level of mercury, regardless of in which form it is present (Metallic mercury emits vapors you can breath in, the forms that don't dissolve in water are still unsafe, even when injected and with that hard to get excreted from the body). Should even a rationalization fail, they move on to either the burden of proof or the appeal to bureaucracy (or appeal to studies) fallacy.

To your problem, I think it's worth it to raise awareness. In order to fairly convince someone, use scientific studies to back the arguments up. Media has been going on to tactics that have been useful. Just like many others, I don't trust the media.
You'll get invited to some discord servers where you can find more contacts, maybe that will help.
https://discord.gg/rpwCTWz
https://discord.gg/kZuhMun
https://discord.gg/pBqZ5b3