Game Crashing - ACT 3 / Black Chambers - testing pit

The game crashes soon as the character crosses the threshold into the testing pit (boss arena).

After restart:
login to the game, attempt to login to the character (currently located in Black Chambers - testing pit), game crashes.

after some time when the instance resets, I can login to the character, at the checkpoint near the testing pit, however, soon as I try to enter the boss arena, the game crashes again.

tried to change DX12 to DX11 and to Vulkan, doesn't help.

Was same issue
after verifying integrity of steam client - all resolved well

Same happen to me, file integrity check helped my character that was stuck in the black chambers (instant crash on load in). Other characters had no problem loading different zones.