This quest is not available in game.
Retrieve a Dark Iron Script from the Dark Iron dwarves near Helm's Bed, and return to Muiredon Battleforge in Ironforge.
Before I fell in battle, Muiredon and I had almost defeated one of the Dark Iron spies near that small house. We witnessed their captain passing orders to them, and sought to kill him and take the orders.
Some of the council in Ironforge do not yet believe the presence of Dark Iron dwarves exists in Dun Morogh. By attaining one of those scripts, we'll not only have proof of their movements, but possibly an idea of what they're planning.
Get one of those scripts and take it back to Muiredon, <name>.