You have repelled the half-orcs and ruffians in the Gladden Fields, but it is your discovery of Sharkey's true identity that will be of greatest interest to Radagast.
'Ah, good! I am glad you've returned, Player. You have been a great help to me!
'My sparrow delivered the water sample you gathered to me, my bunting told me of your victory over the Orcs, but my thrush lost sight of you. I'd begun to worry that Sharkey proved a more formidable foe than I'd been led to believe! Is Sharkey defeated?'
You explain to Radagast that the leader of the ruffians in the Gladden Fields was an old half-orc named Garmog, who impersonated Sharkey in an attempt to amass a small fortune from the lost relics of the Gladden Fields.
'A half-orc? I had heard he was a Man, but now it seems that neither is true. Who is Sharkey?'
You tell Radagast that Saruman is Sharkey. Radagast falls silent for a long while.
'Gandalf told me that the Onodrim have imprisoned Saruman in Orthanc. Is that not so?
'When there is time at last, I will ride to Orthanc and question him myself!'0/1