playing in pc, version 1.3.3, no mods.
In the last quest, an oath is an oath, and hans just stops in the middle of the journey. video of bug attached (bug starts in 40 second mark):
Hans is a savage
I know right 
First he does a u-turn on our journey to show me who’s boss…
Then decides halfway to break my game and dismount (fK this ST, im out!)
Finally, i hit him with mace swings towards the end of the video and he just stands there taking it like a god.
#Savage