Stuck in mainquest: monastery's countermaster assistant bug (spoiler) ((Working again))

Allright so I’ve been around the land for a while before returning to the mainquest, and now it appears I’m stuck and have to start all over again. Because after a certain quest, one of the character needed is missing.

First, I did the quest given by Lord Davish (House of God) to investigate the problems in the monastery building. Turns out that the culprit was the countermaster assistant and I had to pursue him. I went to a mill where he was suppose to look for someone to murder. He wasn’t here, nore the person he was looking for, but the quest updated and was completed, so I wasn’t really suspicious, I thought it was that he had allready fled, and that’s all. So first bug here (given what I had read thus far).

Now days after that, I’m back to the mainquest, and I have to investigate why quicksilver is “missing” from the monastery. And I’m supposed to talk to the countermaster, and he tells me… to ask his assistant. Second bug here and apparently I’m stuck.
The marker indicates the location the assistant was before I completed the quest given by Davish, but of course he’s not there. I had talked to everyone in the monastery then so I guess they knew he was gone, but not now apparently and I have to talk to a missing NPC…

Mainquest definitely broke, or is there a way to continue?
EDIT: remembered his name: Zmola

EDIT 21th february: I tried one more time after last patch downloaded, and the guy who replace Zmola is there, so I can continue the quest. I’ve never met the guy before, even after talking to everyone in the Monastery. I guess the patch put things back in order, or something like that. Problem solved for me, and for future playthrough too I hope!