What is the main story introduced in Chapter 31, and what introductory elements precede it?

Chapter 31 of the Shri Sai Satcharitra begins by recapping several previous stories, including the fulfillment of Madhavrao's vow, the tale of the Saptashringi devotee, and how Sai gave darshan in a dream for Khushalchet Ramlala. After this brief narration of past events, the chapter introduces its primary narrative, which it calls a "wonderful... natural story." This central story, as outlined in the chapter, concerns a sannyasi from Madras named Vijayananda who is on a pilgrimage to Mansarovar and ultimately attains liberation through his encounter with Sai Baba.