Baldur's Gate : The Sword Coast Chronicles : NWN2 Persistent World

The frantic woman in Wyrm's crossing give an encounter to find her daughter in the well, but the daughter never spawn.

I made this quest myself.

Most of these dynamic encounters, unfortunately, don't seem to work (outside of "find the item" and "kill the monster") and Dedude has since retired so he's not around to troubleshoot what's wrong with them.

It might get picked up by another dev one day who fixes it up, maybe, hopefully.

I dwelled in scripting in nwn 1, the errors could be a couple things:

Spawning in an outdated version of the well resref/tag area;
Incorrect resref of the spawning NPC or the NPC got deleted and so it cannot spawn it.