I have gotten to the point where I've taken care of all the foreign assassins (at least, that is what my quest log is saying.) When I visit Sketch on the Docks at night, there's a lovely quest marker over his head but I cannot speak to him no matter how much I assault him with my cursor. I believe he did speak to me briefly once, but I may have ESC'd out of the conversation too quickly? I am not sure.
My neurotic compulsion to finish all quests available to me means this entire thing is aggravating.
Did I miss an event trigger somewhere? Is my quest bugged?