questline bugged

I'm leveling a witch and am currently at level 52. In the story, I'm at the quest point "The Search" - Find Tavakai, in Act 4 "Heart of the Tribe."
I killed the final boss "Tavakai." I'm standing in the boss room and normally "The Hooded One" would appear. The two have a dialogue, then the quest line continues. But nothing happens. Tavakai stands to the left in front of the statue, The Hooded One takes the weapon and that's it. Both remain standing without any dialogue. The quest series does not continue. I can't do anything. I tried to reset at the pillar, went back into the arena, and now none of the NPCs are in the boss room anymore. But the quest remains open.
Then I teleported to Kingsmarch and took the ship back to the island. This completely reset the region. So I fought my way to the final boss again. This time, The Hooded One appears. Tavakai kneels before him. Makoru is there. But nothing happens. No dialogue. No quest completion. Nothing to loot :(
Please help