I've believed this was Domi Reversi Harald for a long time, and still do.
But, it's possible Harald was betrayed by the army, and then, after being stabbed, he was Domi Reversi'd.
Either way, we know Loki killed Harald, so, Harald survived this, somehow. If they were going to do a coup de ta, though, why the fuck do it in the middle of the day, in the middle of the castle's fucking throne room?
I think Harald has to be Domi Reversi'd here.