Just spent 45 minutes on this quest, thrall was running around in circles, i think he ran around the throne room 150+ times while i was trying to kill the lvl 83 boss as a lvl 75. Sylvanus just dipped and never appeared again after the courtyard battle was won. I have never in my life seen such a bugged quest since i started playing wow in original tbc.
Oh and btw i didnt get quest completion after we “won the battle”…