Laboratory map - Monsters stuck inside/under map object

So i've run Laboratory map for the first time. Its pretty cool, but at the end where the player activates the crank/switch to open the boss arena, rare and normal mobs spawn, some of them get stuck under the crank object it seems. They cant reach the player but some extra mods such as Ancestral Bond can still spawn. In the case pictured below, about 5 or 6 rare monsters were stuck under the floor, only visible via mouse hover-over.



https://imgur.com/9e2OBRQ

I just want to verify that I also ran into this just now.