I've just been told by someone that misting snakes will give them RIs (I get how this would happen with a lot of snakes, but the one we're talking about is a BP whose humidity is hard to keep up without misting)

I'm assuming this is total BS because literally everyone seems to mist their BPs- I've never heard of it harming one as long as you don't let it get too high. Plus they're from the FB group "Ball Python Enthusiasts", which on top of being sceptical about 99% of FB reptile groups I've read some pretty bad things about.

If this is true I'll stop right away and try to find some alternatives :)