I earlier posted that the stronghold queens seemed to drift away and Inc said that players might be doing that in order to prevent someone from killing the levi.

However, I think the queens are bugged and seem to drift away on their own without any player involvement. They are unable to fly towards the dent and instead sort of getting pushed away by something invisible.

Here's a vid of them doing it: https://youtu.be/Ywu0RRvxlv4

I was stationary at 0:08.

This should be addressed in recent updates.