Benedictus Bugged, Unable to enter excavated site

Bug Report ID: #3794042911

When the fight originally started, the dialogue between the countess and Benedictus was muted and didn't occur. They still went through the animations.

After killing benedictus, the game froze, loaded the Grinding Gear icons, then started again.

Benedictus area of effect spell went off while he was dead, then killed player character.

Cutscene after killing Benedictus began, dragged his dead corpse to the spot for the cutscene, and when completed the Excavation site never opens.

Respawning at checkpoint results in Benedictus starting his dialogue for the fight, then flying off the screen to disappear into oblivion.

Update:

On further analysis, when starting the fight, I used a Support Skill Gem to look at skills.

Update:

Resetting the instance allows the fight and progression to continue.