

The quest is called "Bridges of Oppression"
I have the same problem. I kill the two guards on the bridge before doing this quest and smashed a pot next to the merchant they were by that dropped a snake that killed the merchant. Problem is when you take the man to the top of the bridge those people have a talking sequence that should happen and because there dead the game just freezes. Thought they would respawn after awhile but it's been like a week and still nothing.