The Unseen Blade - Bug

I was in the middle of “The Unseen Blade” quest as an Outlaw Rogue, and I was on Stage 9 out of 10. I picked up the Kingslayer daggers, and then I got disconnected from the servers last night. So, I got the daggers, spawned outside of the Stormwind Gates; however, when I try to go through the Gates of Stormwind, it makes me do the quest all over again. Then when I get to Stage 9 when I have to pick up the Kingslayer daggers, it doesn’t let me because I already have it in my inventory. There’s no way I can finish the quest, and now I’m stuck in a loop every time I go through the Gates of Stormwind. I tried every possible solution (try to finish the quest, change my Specialization to Assassin in Stage 9, changing my Specialization to Assassin and then try to complete the quest, Hearthstoning out of the quest then go through the Gates of Stormwind from behind and then come back in). Help!