Diplomacy quest "Traps of the Trade - 10183" I think Hjalnar (loc: 53111, 24260, 50910) is suppose to turn into a follower or follow the player or path some place.
He completes the quest and then there are no follow ups. My assupmtion is there is a continuation of the questline after the escort but the script is from 2018 so perhaps the fuctions are obsolete now.
-Zukan