Stuck in the quest "The Battle For The Undercity"

Hi. I have logged in in my acc and there was no one in orgrimmar. Then i went to undercity and realised that the hole city was empty, just like orgrimmar. I know the quest and i know that i need to kill the boss in the throne room of undercity, but there's no one there. I cant start the quest, cuz i don't have it. I don't know if i had abandoned it before and i cant remember now, but....i cant do anything about it now. The hole orgrimmar, durotar, and undercity are empty, and i cant buy the pvp gear. Please help. If the staff of Warmane can bring back the old situation with the old ogrimmar and etc. without doing the quest, ill be very thankful.