This time you need to collect 10 samples of Scathecraw from around the Island. This is one of the most common things that can be found.
This can be found throughout Raven Rock. If you have 10 collected already, then you can simply turn this objective in.
Once you have all 10 samples, return to the Riekling Chief. He will do a little dance in his throne and ask for help with one final task. Agree and he will bound outside.
Time for you to help them kill off the Nords that they took the hall from. The Rieklings will gather outside the Mead Hall. The Chieftain has plenty to say before the group comes together and moves on their foes.