While I have reported this in the /bug form thought I would see if anyone else had this problem and how they got around it, if they did.
While doing the quest in the dream world to find the heart piece, I died at which time the Golden Knight; who was supposed to be helping me clear the pathway; disappeared, never to return. When I got to the end of the quest area; and after Nocturnal shows up and banishes the other two princes; you are supposed to hold off the bad guys while Valsirenn opens a portal to exit the area. Bad guys are dead, no portal, and she isn't even trying to open one. Tried quitting and logging back in, nothing. Quest is at a standstill. Even exiting the area via the map does no good as the quest pointers don't update and just direct you back through the dream chamber and back to where you were.
I'm thinking it may have something to do with character death and the Golden Knight disappearing, but who knows. The patch notes show they patched something to do with graphics in this quest, so maybe they broke something else. Frustrating.