I want to join the thieve's guild and i have to enter the ratways and find Brynjolf at the inn there. Now there's only one entrance to the sewers and two guys are standing there blocking the way, after their conversation i can sneak past one of them, but the other one is facing towards the tunnel and is 100% detecting you.
Now to my question, are these two of any importance to later uests, or even members of the guild? May i just kill them (they attack on sight) or do i have to use an invis potion or something like that, if i dont want to mess up any further thieve quests?
And what's with the guy at the table in front of the sewer tavern, is he of any importance?