Can you tell me about the group of devotees from Madras who visited Shirdi in Chapter 29?

Certainly. Chapter 29 recounts the arrival of a group of devotees from the Madras region, now known as Chennai. These travelers were on a pilgrimage to Kashi and made a stop in Shirdi to have Sai Baba's darshan. The text mentions that they belonged to the Ramdasi sect and had spent the year engaged in devotional singing, which they performed with great enthusiasm in Shirdi. Upon taking darshan of Sai, they attained peace and stayed for several days. Pleased with their devotion, Baba gave them a gift of eight rupees and eight annas.