Back to Skellige
Between the village of Blandare and the Miner’s Camp to the north you’ll come across a Cyclops by an upturned wagon.
Kill the Cyclops and examine the body and the dead horse. The search marker will be expanded. Search the other side of the road to find footprints and a trail of blood. Follow them to a group of Nekkers. Continue on to find another body with a Letter to Yanne.
Take the Letter to the blacksmith, Yanne, at Kaer Trolde. He’ll ask you how you found the letter. If you tell him the truth he’ll thank you for informing him. If you tell him he’d rather not know then he’ll assume you robbed and killed his family and will refuse to do business with you.