Shadow Labyrinth Boss 1 (Ambassador Hellmaw)
Do not fight this guy in the room where he is chained, fight him in the hallway behind him that leads to To'gun. This will help with getting too spead out during fear and is also helpful for directing the acid cone away from your squishies.

Shadow Labyrinth Boss 2 (Blackheart the Inciter, a.k.a. Assface)
Again, positioning is vital, fight him in one of the corners to the left or right when you enter the vestibule. This will save time when punted as you will likely hit a wall and keep the group tight during the MC when you are fearing yourself. As long as you can snap back agro to your tank and get everyone refaced you should be okay.

Mechanar Boss 2 (Nethermancer Sepethrea)
You're kinda screwed on this one because of Mind Flay hampering movement. Don't think kiting to Calculator's room works anymore so this may come down to fire resist. With your dpsers keep them clumped and do some shoot and scooting, it's inevitable that they gonna get hit or have to walk briefly through a fire trail hence FR being a good idea. When they start puffing you go balls to wall. Just pray your tank doesn't get targeted by them. Pretty sure the disorient of her fire breath thing can be removed and agro re-established pretty fast by your pally.

Don't have enough experience on Botardica to say