Make your way to Veil Shalas with all haste, <name>! Time is of the essence here. If the arakkoa discover what you've done to their defenses, they may attempt to move Dugar, or even kill him.
If you can, bring a friend or two with you. It's likely to be rough there. The bird-men have gone to great lengths to secure their prisoner and they're not likely to give him up easily. After you've found Dugar and dealt with his captor, return to Stonebreaker Hold and notify Rokag.