You can always disprove a false claim by showing the truth.
In your case, your specific claim was that the connection between vaccinations and autism is disproven.
It was not. A person high up in the research has come forward to testify that the report put out selectively ignored all contradictory evidence and falsified the result to protect big pharma.
Your claim is invalidated.
Reference your claim that you can disprove a false claim:
Prove that as a teenager, that you did not repeatedly drug and rape girls.
How would you disprove that?