I've been having same issue, but it's not just in gravships, for me there's a chance every time a pawn casts magic indoors. I had a summoner with auto-casting summoning minions, and I started noticing that they'd get random injuries due to roof collapse, then I noticed it live. Particularly this is a problem for me cause I'm trying to build a base in a mountain...
I think this became an issue since Odyssey got released, so it seems like there's an odd conflict...

Also had the same issue. Chef autocasting buffs and injuring people. I wanted to post the dev logs but could never find the exact incident.