Bug Can't Progress "Ascent to Power" or Access Trial of the Sekhemas

I’m stuck on the "Ascent to Power" quest in Path of Exile 2 (endgame, post-Act 6). I discarded Balbala's Barya (green quest item) after defeating Balbala, The Traitor in Traitor's Passage (Act 2). Now, Balbala doesn’t drop the item again in Act 2 or 5, and I can’t progress the quest with Zarka at Ardura Caravan or unlock the Trial of the Sekhemas waypoint. This prevents me from accessing the Trial of the Sekhemas. I’ve tried killing Balbala multiple times, disabling loot filters, talking to NPCs, and joining a friend’s portal (game says quest not progressed). How can I obtain Balbala's Barya, progress the quest, or access the Trial of the Sekhemas without starting a new character?

If you haven't taken the quest item (or dropped it), then (at the current state) the quest is broken.
Then your only chance to get ascendancy points is to play The Trial of Chaos (Act 3) with Inscribed Ultimatum (and enough "Number of Trials"): Ascendancy class.