I try to use this option as little as possible, as it feels not just cowardly, but is mechanically and logistically weird. But I thought I'd give it a try when Astarion, trying to sneak through a hostile Goblin Camp alone after fast-travelling there, got spotted.

The only enemy that spotted him was the named Bugbear (Bo'kor'ok'uk or whatever). Astarion was able to flee fairly quickly using Dash.

But when my full party returned to the camp, Bo'kor'ok'uk (or whatever) was *gone*, poof! All other goblins, as far as I'm aware, were still around. Is this a bug?