Did you read over the requirements to trigger the quest (
Read Here ).
If you completed Head Hunting, and talked to Azeran, than it could be a map loading error. Staying at an inn should solve the issue.
Lastly, what device are you on?
I know Apple has v1.2 or something, so it's a major update behind everyone else.
I can't remember if the Haunted Galleries are part of the Apple version of the game.