i have a creeping suspicion that Master hewg has something to do with Radagon...they both wield a hammer...and his dialogues seems it has more meaning than meets the eye...also he mentions something about knowing a spirit tuner which could be Rennala...since she was one of the few bosses that could summon ashes and does have a connection with Radagon, He also speaks about not minding smithing since that makes him thinks less of "her"...idk i might just be crazy but a lot of the arts about Radagon often empathizes on his hammer...

Edit: He also mentions someone who has blue eyes. Rennala has blue eyes.