Evidence supports Gwilum's beliefs that the Warg-riders plaguing Carreglyn are in fact servants of Saruman the White... and that his own rulers are in league with them.
'Besides small raids on our herds, the Warg-riders do not seem to care much about Carreglyn. Perhaps they are here only as a stopping point on their march northward, or perhaps they are hunting for someone specific... like your Ranger friends.
'It may be that the goblins at Naur-maudhûl carry orders which might enlighten your friends. While you are at the Warg-camp, be sure to search any goblins you defeat there and take any orders you find to the duvodiad encamped beneath the eaves of the Gravenwood.'
White Hand orders might be carried by goblins and Warg-riders at Naur-maudhûl, north of Barnavon.
Gwilum told you to search for orders on the corpses of the goblins you defeat at Naur-maudhûl.
Amlan is at his camp beneath the eaves of the Gravenwood.
Gwilum told you to take the White Hand orders to Amlan.