bottom left of the sand map there is a town with monsters. In one of the houses is Rud’s family. You have to complete his quest line, otherwise the door in the town will be locked.
Yes, Tearn turned up in Tailor after helping Rud’s family, and you received a new quest: to free the three captains. But there is some bug at this stage, because as before, after releasing the captains you don’t get another quest.
Edited: I replayed the sequence from another save file, then it worked. So something must have affected the save file from which I got stuck.