Not too sure about melee But in general keep this in mind
Ground phase :
1. watch out for the big swirly circles at all times. I remember hearing he has a huge hit box ,so u can dps from a range and dodge the swirly circles as they come at you. The melee probably died because they got a high sound from this
2. Keep watching the timer for his breath thing , and make sure you move in the correct way if you are targeted. Fail and ull probably be named and shamed
3. Air phase Keep moving, if he targets you, sprint. Dont stand in the fire
In our runs, melee seemed to avoid the rings much more effectively. I think it's due to the mechanics of melee dps. You don't have to stand still to dps and he has a hit box the size of Stormwind. Ranged dps and healers tend to try to get the cast off and get hit.