Can you walk me through the entire story of Cholkar's vow, from his initial promise to the final outcome in Shirdi?

Certainly. The story of Cholkar, as detailed in Chapter 15, begins with his vow to Sai Baba. He was from a poor household and needed to pass an examination to secure his job. He promised that if he passed by Baba's grace, he would visit Shirdi and distribute sugar candy. After passing, he faced financial difficulties, described as the 'threshold-ghat' of home expenses, which delayed his journey. As a personal penance for this delay, he gave up sugar entirely. When he finally made it to Shirdi, he fulfilled his vow by distributing sugar. The story culminates when Baba, who did not drink tea, instructs a man named Jog to serve Cholkar tea 'well-filled with sugar,' proving to Cholkar that Baba knew of his secret sacrifice all along.