Ive been playing for quite awhile now, but as I am trying to go through quests ive missed through natural exploration, Ive had issues getting this quest and Forsworn Conspiracy to start. I am playing on the 360, and I arrived in Markarth via the Night To Remember quest. This quest is supposed to start with a conversation with Vigilant Tyranus, but Ive never seen him anywhere in Markarth. The Abandoned House is locked by key. Is there another way to trigger this quest, or to bypass part of it?

Similarly with Forsworn Conspiracy, i see the two people involved in the scene in the market, but they dont do anything. on the other hand Id found the journal before i went near the market, and going to the shrine starts the final scenes, so that quest isnt completely buggered up for me.