You think they don't know?
Yes. In fact, I'm certain they don't. You have to understand, Trump voters don't live in our reality. They live in a fabricated fantasyland created by the slop media they consume. They think Donald Trump is fighting the pedophiles, because that is what they have been told to believe. All of the attacks on him are "fake news" because they're from mainstream media sources, which they have been told to never trust.
If concrete evidence that they have been directly lied to is distributed to them by a source they trust, I can't say for sure what would happen, but it's probably the best chance for them to be deprogrammed.