Missing Weapon Set Passive Skill Points

I am currently at 20/24 weapon set passive skill points. All visuals on the world map show that I have collected all the points (X over the objective icon), but I am clearly missing something and/or something is bugged. I went back through the campaign to re-acquire the points in case something was checked off that I didn't receive the reward for.

The following are the passives I checked:

ACT 1:

- Killed the Crowbell in the Hunting Grounds
- Visited Una's Hut in the Ogham Farmlands and talked to Una in the Clearfell Encampment. It is not possible to find another lute.

ACT 2:

- Killed Kabala, the Constrictor Queen in Keth
- Checked Lailuma's corpse in Deshar for the Final Letter and spoke to Shambrin in the Ardura Caravan. It is not possible to find another letter.

ACT 3:

- Killed the Mighty Silverfist in the Jungle Ruins.
- Killed Vaal Goliathsdial to check for the Sacrificial Heart drop. It is not possible to find another heart.

ACT 4:

- Spoke to Tujen in Kingsmarch and killed Captain Hartlen in the Journey's End. It is not possible to get more Verasium spikes.
- Killed Yama the White in the Halls of the Dead.

Interlude:

- Killed Oswin in Wolvenhold.
- Killed Akthi and Anundr in Khari Crossing and spoke to Risu.
- Killed the Abominable Yeti in the Howling Caves.
- Spoke the Hooded One in every town in every act.

I'm not sure what else I'm supposed to do. Is there any way to better check what I am missing?