What story is told in Chapter 34 of the Shri Sai Satcharitra to illustrate the power of Udi?

Chapter 34 continues the narration on the glory of Udi by telling a specific story about a doctor from Malegaon, in the Nashik district. His young nephew was suffering from a terrible bone-cyst, known as Hadyavran, which no medicine could cure. Despite the efforts of the doctor, his physician friends, and even expert surgeons, the boy's condition showed no improvement. Having exhausted all native and foreign treatments, the family heard about the great saint Sai Maharaj of Shirdi. As recounted in Chapter 34, they decided to visit him as a last resort, hoping that the application of his Udi could cure the seemingly incurable disease.