I had the same thing occur, and I believe I know why. Playing as space marines, my tactical marines were infested by pink horrors before fleeing. Later, they were enslaved by the enslaver overlord. After killing the overlord, I got my marines back, but when they died, I now had pink horrors under my control. This was quite random, and funny for my multiplayer group, so I really like this even if it's an unintended bug.

Also, it makes zero sense period why the daemons are able to infest Tyranids. I even get the vehicles and such, since they technically still have a "soul" that can be corrupted, but there is factually no good reason that Tyranids get this. They have no soul, no mind except The Great Devourer, and are all bred for one purpose.

I've had the same thing happen with the pink horrors, idk if maybe I can edit the files to remove that.

Hey thanks for all the great work you've done on this game! I have an issue though that I'm wondering if anyone knows about. When I play as the Tyranids, the pink horrors somehow became controlled by me when one of my infected units died I guess and then I could use them to make a pink horror horde of my own. Not sure if that's an issue with this mod or some conflict on my end. Just wanted to let you know if its something related to this mod.

what he said

Are you responsible for every mod for the game? Seriously good job man

Thanks for the addon, my game isn't remotely balanced anymore so I am not worried about them being strong :)