Make your way to Legion Hold and locate the Legion Communication Device. While standing near the communication device, use your disguise and learn about the Legion's plans. Return to Wing Commander Nuainn at Wildhammer Stronghold when you've completed your mission.
The fortress of Legion Hold is nigh impregnable, and to be completely honest, I can't spare the forces for an assault. Our hopes are riding on you, <name>.
What little information we've been able to gather indicates that the Legion stocks and prepares its infernals at the hold. With the help of a disguise I'll give you, you must sneak into Legion Hold and learn about their plans. Your best hope is to intercept or overhear communication between their commanders. Good luck, <name>.