After talking with Lump and getting the horn, I had my party run down to the fallen tree that gives you access to the goblin camp.
I told Tav to jump down and as the others were jumping down, and Our dear Gith friend l Decided to fall into the rocks behind the tree. When I switch characters and told her to move toward the tree, Tav followed her and the ran under ground but pathfinding along the trail back up toward the main bridge.
They then both auto jumped into the ravine and died.

Couldn’t reach the corpses but luckily you are allowed to fast travel as a spirit. Lol