So just tried this dungeon for several hours. Gonna try again soon.
We tried first with 5 chars (Enu, Eni, Panda, Cra, Eca), sadly the extra mob his very hard to control. He jumps around a lot and putting him into gravity state doesn't prevent that.
We tried after with 4 chars (Enu, Eni, Panda, Eca) and it seemed way more doable to control the various mobs. At some point we got the same setup as She-Devil with the panda taking care of the boss down the map. Sadly we made one mistake and Bandjid was able to kill us.
The +50% final damage is atrocious, one small mistake and you're dead.
Found this from the french players, 8-man team and finished in 28 mins.