When starting the fight in the quest, Me and some of my men are spawned outside of the city walls rather than in the city (the city being Amprela), and I have to manually deal damage to the city gates without help of my men (as they are walking as if they are inside the city). The mission was given by 'Tessa the Maid' if that helps. I have also found that this happens when getting into a fight with a gang by killing gang members in a clearing/waterfront etc, though I don't remember which cities it happened in.