An Allu'thoa high shaman is in the Allu'thoa village Gazanti at possible locations ( -1076, 124, 1070 ) Copy/waypoint -1076, 124, 1070( -1049, 92, 944 ) Copy/waypoint -1049.21, 92.28, 943.50( -1150, 101, 950 ) Copy/waypoint -1149.73, 101.43, 950.41. The named spawns at the same places but does not give the update.
Use the Corrith's Barbed Grasp on it; it de-aggros and returns to its spawn spot. Left click to "capture" it.
Return to the beach camp - quest updates when you get near Corrith
Speak to Corrith, then interrogate the captured Allu'thoa.