There is either a bug here, or I don't get something. In Fort Deadlight I messed up the stealth part at the beginning got a castle wide red alert and everyone was attacking me. So I cleared out the castle. Apart from the people in the jail, now one was talking to me, everyone was hostile.
Before going to the court Serafen told me that he had some quarrel with Syri and it might not end up well. Anyway, even there everyone attacked me, there was no one to talk to. I don't even remember if Syri was there, whether I killed her or not. So the quest seems to be stuck here. Syri is not there to talk to here and I did not find anything relevant in the rooms there.
What do you think?