I'm doing DG quest on vampire side for my 2nd character. When I went to dragon bridge, since I sided with stormcloaks, there were only stormcloak soldiers there instead of usual Solitude like guards. Because of that, there were no guards around except a single stormcloak soldier I could not talk too. Luckily I already played DG on my first character, and knew where to go.

I just thought I would post this here to let Bethesda know.

I saw this too and it seems no one gives you the information where to go when there's Stormcloak soldiers. Like you said though, if you know where to go you can pick up the note off the vampire anyway and the quest will continue.

Yeah, its like the opposite of how the blood on the ice quest would be where you couldn't do the quest if you completed the imperial side, and the female stormcloak soldier would no longer be there at crime scene.