Just rolled molten furnace and proceeded to champion dredge where the voice commands triggered, however the fractal did not proceed and the group had to disband.
I heard that you cannot enter the room before the NPC’s, however when someone was standing outside (to avoid this issue) Rox and Braham just aggro’d to the person outside, forcing all of us to enter and alas, the bug encounter.
During this fractal, Rox and Braham appeared to have not fully entered the area where this final event takes place. After a party whipe to try to reset the NPCs, Rox and Braham then entered, however they would aggro to someone and just follow them around the area without triggering anything.