Unique Map - The Silent Cave BUG

There were 4 small essences and 1 boss essence. I killed 3 of the small onces and then did boss. It did not grant the skill points and I am unable to do the last Essence as it does not interact. Map Objective still says Defeat the imprisoned Boss which is already dead!

There is clearly an issue with doing boss before the essences and should be an easy fix in code....

Too bad these unique maps ain't many or easy to find!!!