No way we could effectively speak for what all members of a group think, and it would be foolish to try. But in speaking about that group, it is quite clear that profound misunderstandings of autism and of immunizations exist in staggering array.
Given the unparalleled historical track record of the success of vaccines, there is simply no coherent explanation to deny their benefits outside of base ignorance or willful STUPIDITY. Look who the anti-vaxxers are. That investigation alone should shed some light on the situation.