Who was the Agnihotri from Nashik, and why is his story introduced in Chapter 12?

Chapter 12 introduces a story about a ritualistic and orthodox Agnihotri (a keeper of the sacred fire) from Nashik, with the surname 'Mule.' His story is presented as a 'delightful story' that illustrates the greatness of the Guru. The chapter explains that he came to Shirdi due to the strength of his past merits, as one cannot stay in Shirdi even for a moment without such credit. It is mentioned that his original intention for the journey was different, but a fortunate coincidence led him to gain the benefit of Shirdi and to have a sight of his own Guru, setting the stage for a lesson on Guru-bhakti.