Can you explain the series of events that led to Dev's confusion about the Sanyasi's identity at his Udyapan ceremony?

Dev's confusion arose from a prior, unrelated encounter with the same Sanyasi. Chapter 40 explains that before Dev even extended the invitation to Baba in Shirdi, the Sanyasi had visited him to collect funds for cow protection. Because this initial meeting was for a worldly cause, Dev categorized the Sanyasi as a fundraiser. When the same person later appeared for the meal, Dev's mind did not make the connection that this could be Baba in disguise. Dev himself later lamented this delusion, admitting that if the Sanyasi had only appeared after the invitation, his 'vision would not have been so confused.' He also forgot Baba's key phrase that 'two others will come with me,' which should have served as a clue.