I'm not commenting on the oathbreaking part (since I'm not a fan of the system to begin with), but in this case, could this be because they only implemented for the oathbreaker dude to appear at the surface camp? So, you would need not to be indoor or underground?
Good thought! I’ve just checked as I do have a save with a newly broken oath in Grymforge from an earlier playthrough. The oathbreaker knight does appear in my Grymforge camp but he’s down some steps away from the main party area (still near Withers) so could be easy to miss. But I’d broken and paid to restore my oath earlier in the game, so couldn’t check out the cutscenes in this scenario as I think we only get them the first time.
