BUG: Navarran skull pile disappeared

Did you already pick your specialization?

IIRC not possible to loot it if you already specialized in another class.

Nope.  I was only working on Necromancer and the last bone pile didn't spawn correctly for some reason and now I can't complete the quest at all.

It should respawn correctly upon reentering area.

Just return to Skyhold then travel back on the spot.

This also helps in Cassandra "unfinished business" sidequests that won't complete if you kill mobs without her in the party, so you need to return to those spots with her in the party (the game respawns the whole group of mobs).

EDIT:

You did revisit the area and it didn't respawn?

Okay, go to the Orlais Capital. Wait I'll post a map where. You should be able to buy it at a certain shop. Just a sec.

EDIT2:

All unlooted books and stuff from major quests should be obtainable here at this merchant:

http://s30.postimg.org/4bjfhmlzl/pic.jpg

If it's not buyable there, then it's definetly a bug and your only option is to pick another class then. ☹️

I've tried leaving and going back, but nothing is there other usually a couple darkspawn wandering around.  All the other spawn sites are also empty.

I'll try the merchant though.

Edit: No dice at the merchant.