No unique map skill book

Bug Report ID: #1319726122
Completed the silent cave unique map with a t15 waystone. My UI says that the map is still incomplete, despite all the enemies being dead, boss included. Did die to map boss twice.

Mods on the map besides the unique map mods:
50% more Rare monsters
patches of ignited ground
22% quantity
32% rarity
25% waystones