'RFK has never sought a briefing from anyone in CDC on measles, or any of the other diseases he often talks about, since he's been in office despite repeated offers being made to him to do so'

Cranks see experts as enemies, not colleagues. If they actually did encounter information that broke the fugue state of their delusion their entire world would collapse. Their identity is utterly nullified. It is why they are impervious to argument and data. For a scientist those are their identity.