Who were the uninvited guests that ate at B.V. Dev's feast?

The uninvited guests were actually Sai Baba in the guise of a Sanyasi, along with two unnamed companions. Baba had promised Dev he would come to the meal with two others. As Chapter 40 explains, Baba fulfilled his promise by arriving with two people, but a "veil of Maya" prevented Dev from recognizing him. Dev simply registered them as "some guest who has come to get a meal," failing to realize it was the very saint he had invited.