I had the same problem. What worked for me was to fly to Silithus (from Stormwind) to turn in the quest to Magni. Then I could come back to Stormwind and do the Black Empire Campaign again so I could get to Boralus.
I had the same problem. What worked for me was to fly to Silithus (from Stormwind) to turn in the quest to Magni. Then I could come back to Stormwind and do the Black Empire Campaign again so I could get to Boralus.