The text states a saint came to Shirdi with a wedding procession. Was this saint Gajanan Maharaj or someone else?

The saint who came to Shirdi with a wedding procession was not Gajanan Maharaj. The provided text from Chapter 0 is very specific about this series of events. A Muslim gentleman named Chandbhai met the saint in a forest. After the saint helped him find his horse, he stayed at Chandbhai's house and later accompanied his family's wedding procession to Shirdi. It was this saint who, upon being greeted by Mhalasapati, became known as Sai Baba. The name Gajanan Maharaj does not appear anywhere in these passages.