Child's other mom is turning my kiddo anti-science and anti-vaccine. Help me fight the good fight!

My 11 year old spends 50% of his time with an anti-science and anti-vaccine family. Single parent me (in Ohio) doesn't have a lot of support when I've tried to help fight some of those thoughts he's been brainwashed with in the name of religion. I'm christian, but his other household is extremists. "You believe in science too much" and "cavemen never existed" are things he's said in the last year. He's a straight A very smart child, he's just been brainwashed and I want to try to help him before it gets worse.

What kinds of shows, books, documentaries can I expose him too to make him think more critically about some of these things so he understands science is real and vaccines work?

He does get into Veritasium on YouTube, so I feel like that's a step in the right direction for science and critical thinking.

Thanks in advance for your help!

Cheers