Can you tell me about the Yogi who came to see Baba in hopes of achieving Samadhi?

Certainly. Chapter 23 recounts an incident where a practitioner of Yoga, who had thoroughly studied the Yoga Shastras of Patanjali, came for Baba's darshan with Nanasaheb Chandorkar. Despite his deep knowledge, he was unable to achieve Samadhi for even a moment. He held the belief that if Sai Baba, a 'King of Yogis,' showed him grace, his doubts would be cleared and he would surely achieve the meditative state. However, when he arrived at the Masjid, his spiritual expectations were met with the mundane sight of Baba eating bread (bhakar) with onions.