I picked the "You erred on the side of caution and kill both potential traitors" on the On The Trail Of The Traitor Quest and when I go back to the abbot, the only option I get for him is to let him know about Marisol. The conversation ends and it still shows that I still need to talk to him but get no option to move forward and finish the quest. I have tried previous saves but unfortunately do not have one before I killed Marisol and the Provost. 

I'm stuck at a similar point.  When I go back to Abbot, I've told him about a message from him to a conspirator of Seer Wiley, and it just leaves the conversation.