Before Baba came back to Shirdi with the wedding party, were there other saints living there?

Yes, the prologue of Chapter 5 of the Shri Sai Satcharitra explicitly states that Shirdi was already home to other holy men before Baba's return with Chand Patil's wedding party. The text mentions that a saint named Devidas had already made Shirdi his home for some time. Furthermore, another saint, Janakidas Gosavi, had also come to live in Shirdi. This detail from the sacred text highlights that Shirdi was already a spiritually significant place even before Baba made it his permanent abode.