Cruel Mektul Lava insta killing

I was playing a level 82 hardcore character with 2,965 ES, 1,513 HP, and 76% fire res and went back to this level 62 Molten Vault area to complete the quest and the lava killed me in less than half a second.

Can I get my character back?

https://youtu.be/9YSaQ7ykMDM Here is a demonstration.

The first time I enter is after I had another player come into the instance and test out if the lava was just bugged for me - it wasn't; he instantly died as well. The damage that I take in this first encounter is what I expect from the lava. When I die and re-enter the arena, the lava is back to killing me instantly. This is clearly bugged.

Again, this character was a hardcore character and it died due to this bug