Spoiler
At the quest to go take back Fort Dunstad, the first fort we assault, it has a counter that says "Enemy Remaining 100%." So I gather I have to kill Stormcloaks. The problem? There's not a single solitary enemy in the entire fort, it's completely deserted. And I know I havent' cleared it out before, because when I'm running up to it with the Imperial soldiers, I get the prompt that I've discovered it, the icon on the compass goes from black to white. So I've never been there before. But it's completely empty. Not a single enemy.
How do I get past this quest? And what in the world would cause this? I've tried Google, and can't find anyone else with the same problem.