One Last Adventure

Sailor_Palutena

Both the dog and his owner Viggol doesn't move with you. The dog is stuck in two places. Viggol is stuck on a bridge on the other side of the cave. Once you speak to him, you can find the dog near the remains of a miner. Viggol will disappear and phase in and out near your in the northeast cave, unable to be spoken to.

Sailor_Palutena

Since I cannot edit, the location is:
Zone: Blackreach
Objective: The Lightless Hollow — Help Viggol go on one last adventure.

nankeenheron

I had the same problem. I left the mine via the passage to the NW and went back in, and Viggol and Pickle ran past back to the dead miner. At that point I could speak to Viggol and continue the quest.