You can haggle here if you wish, then head out to the location south of the Border Post. However, he's adamant Mikel can't possibly be dead despite everything indicating it's likely.

If you go to Bruno, he'll explain that his brother, Mikel, took it upon himself to take care of several women that were displaced when the war destroyed their village and had taken them to some old mines for shelter but hasn't returned. And so the spirit was set free, and the dark powers afflicting the Whispering Hillock were dispersed.This quest can be picked up at the Inn at the Crossroads' notice board, which will point you to talk to Bruno inside, or by finding the mine directly.

If Geralt decides to spare the Ghost in the Tree: These whispered words convinced Geralt and, following the spirit's instructions, he lifted the curse, transferring the druid's ghost into the body of a black mare. In doing so he expulsed it from this world for good. Geralt did not believe the spirit's explanation and destroyed its cursed heart.

If Geralt decides to kill the Ghost in the Tree: Yet too much innocent blood had been spilt on the Whispering Hillock. In exchange, she promised to rescue the orphans from the swamp clearing, who would otherwise face a cruel death at the hands of the Crones. The spirit begged Geralt to lift her curse and free her from her torment. The unfortunate locals had died as collateral damage, for, the spirit attested, nature's wrath is unrestrainable and distinguishes not between unwary innocents and unwelcome ill-wishers. The forces of nature she had once served now protected her from the fiendish sisters' further designs. The spirit spoke to him in a woman's voice, and claimed to have once been a druidess who had kept watch over the Velen grove until the Crones murdered her and imprisoned her ghost in the tree. Geralt agreed to investigate the problem, and soon discovered the animals were controlled by a spirit entrapped in a tree growing atop the hill. Instead, it stood for danger and terror, for a place where wild animals, driven by some mysterious power, had killed many an inhabitant of Downwarren. Journal entry The Whispering Hillock – if the world were not as it is but as it should be, this name would denote a place of hidden nooks and lovers sharing heartfelt lies in hushed voices. The Witcher 3: Wild Hunt - Blood and Wine Review

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