Valdo's map bugged. Emperor's mastery cannot be found.

I'm running a valdo's map with abyss and restless dead. I complete the abyss ( i click on the chest at the end), kill the map boss and kill all the mobs. But i have still monsters remains because of the restless dead.. I see a lot of people saying that the abyss is bugged but i manage to finish it so can it be the restless dead ?

bug reference : 2.250.323.978.

Thanks

unsure for valdo map, but for Acton's Nightmare unique maps, monster can be finally killed by using fresh offering or other corpse consuming skill

but it may be more likely the Abyss.