Randomly I headed north to continue a different quest and spotted Prince Azah is actually South East of the Mor Naril Camp wayshrine, so the bug (for me anyway) is a Map Marker one.
I had the same problem, Prince Azah was nowhere to be found in the location the marker for the quest objective pointed at:
But I was able to find him in this location, and the objective refreshed itself as soon as I approached, so yeah I think it's just a map-related bug, here is the area: