Elements of Destruction: Shadow Casting in the Dark

What's the trick to killing Balgros in the quest Elements of Destruction: Shadow Casting in the Dark? I have MC gear (infused and experimented for potency) that was made with purified rares. My only downfall is that I have not been able to reforge my set of gear yet and won't be able to till the 22nd (points allowance day). My potency is 54K+ and my health is around 58 million. I also have MC food & drink. My merc dies very quick and I either die myself soon after or run out of the instance with little time to spare after burning him down to 50%. I've tried rooting, dazing and kiting him around the room. DayBreak help desk is NOT helpful to say the least. They've told me that there's nothing wrong with the instance and that I should look here for answers. I've asked on General chat and all I hear are crickets in the room.

Are you keeping the guard away from you by using the web shackles regularly on it?

That's part of the sig line and I would highly recommend you look it up on Wikia. Once you do, you'll see why you're constantly being defeated.

Hi.. could really use some help here. I did this quest with my healer... and had no problem killing Fathad Zastim, but now i`m doing it with my tank... and i just can`t seem to kill him. Any help please?