When exiting the Predator from King Jo's vehicle mods, the insectitron is destroyed when the setting for entering vehicles while still in the spidertron is enabled.
https://mods.factorio.com/mod/kj_40kpredator

IGNORE This comment<<<<<<< (accidentally replied to my own instead of editing it)

So, this is actually only an issue if the Predator has any momentum when you exit.
It's just running over the spidertron for some reason

You technically shouldn't even be able to enter another vehicle while in one already. I assume this is a feature from some spidertron tweak mod.

Eitherway I don't think I can do anything about this without changing collisions around, and I'd rather keep them the same as vanilla spidertron.