Butt and Ugly decided to have a kid and guess what? Bowelrot was that kid. Seems to favor hanging out right inside the entrance on the southwest side.
Entrance pylons at the time Bowelrot was found in the dungeon.
A new challenger has entered the dungeon! Where as Stratos was the only one I'd ever seen, this is one of the other six bosses of the dungeon. Stratos seemed to always favor the north east corner where as Voidinian here prefers the south west corner in the adjacent room to experiments 7.1 and 5.1
Also, with this boss change it appears to reconfigure these pylons. The amount of broken vs active have changed. IF that is the case, then the moment you enter the dungeon you would know which boss you were looking for and potentially where to find them. I'll update as I learn more.