Hello,
I've found out that you are phased into an empty orgrimmar once you finish your dh quests(after leaving the broken isles). I recall that the dread infiltrator was revealed by the guards when I killed them and died very fast.
To be more precise the quest is Audience with the Warchief
- 0/1 Report to Saurfang
This does probably work for every class but i can't confirm yet.
Cheers