I think i know how I bugged the whole Black Market quest. I have completed everything except the one that is listed on Kiya's site as one of the many way to bug this bundle of quests. "Find the truth about Tingalf." If you have the first letter, from the cave, when you go to Trevor you are given the speech options after he gives you the quest, that would complete it. But i believe you have to wait and save those speech options until after you have the second letter from Pedro, and speak to Lieutenant Robin.
I am quite sure that i remember it correctly, i read the speech options after many times of not looking at it for spoiler reasons, and when i read it i recognized the conversation. I think this is how you can bug the quest and i am guessing there isn't a way to fix it.
I will keep trying but i have gotten pretty bogged down and bored with this section of the game as i keep getting into little situations like this and have to backtrack. Of course i end up deleting in between saves thinking i have everything handled so only i am to blame.
I know this topic is out there in a few places but i couldn't find if you guys had already figured this part of it out. It has truly bothered me and now i think i may have to go all the way back to the darn Vampire!! I might have to pick another game up for awhile before i have the stomach to backtrack so far to try to get forward. I wouldn't be able to play on knowing i missed that silly quest.
