Speak to Mackay Firebeard at the Gorshak War Camp.
I also need ya to seek out Mackay and his men on the other side of the Devouring Breach, at the Gorshak War Camp.
The Dragonmaw didn't survive the initial onslaught, and Mackay's lookin' to ransack what he can of their camp to supply our fight. There shouldn't be much convincin' necessary, but they'll likely want a hand wrappin' things up there before they make their way back to Keegan.
Give'm a boot in the arse from ol' Iain if ya have to.