There is one other post on this but id like to bring it up again as it is really a game breaking bug.
When trying to find Erik in the camp during this quest he is not where he is supposed to be and causes the game to be impossible to progress in. His quest marker is actually hanging out somewhere in the monastery while you are locked inside the camp.
I decided to load an earlier save and went to the said location prior to the quest and found Erik hanging out by himself, he has to dialogue to engage in and eventually the guards come and chase him off. Only to have him end up in the same said location a couple hours later.
Id appreciate a known fix to this, and also if this would be patched.