Can you narrate the story of Kaka Mahajani's skeptical friend who visited Shirdi and what happened to his initial resolutions?

Certainly. Chapter 35 tells the story of a friend of Kaka Mahajani who was a devotee of the formless and averse to idol worship. He agreed to visit Shirdi out of 'clinical curiosity' but on two strict conditions: he would not bow his head to the saint, nor would he offer any Dakshina. Upon arriving at the mosque, however, Sai Baba spoke to him in a voice that was a perfect imitation of his deceased father's. This deeply moving experience caused the friend to be amazed, and as the text states, he 'melted inside.' Forgetting his previous resolve entirely, he spontaneously bowed his head at Baba's feet, demonstrating the profound impact of this personal encounter.