Citadel Not Completing

Full Cleared an Iron Citadel, Boss is dead, got his fragment, but map won't finish.

Still shows 1 monster remaining and his boss icon on map where his corpse is.
Double checked I didn't leave any other monsters.

Map shows in progress still. Even after closing all portals. (Edit: Now shows failed after opening another map).
This was my first time doing Iron Citadel, and the quest finished.

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