According to Chapter 20, what challenge did Das Ganu encounter while writing his commentary on the Ishavasya Upanishad, and what was Sai Baba's initial instruction to him?

Chapter 20 recounts the story of Das Ganu, who undertook the task of creating a commentary on the Ishavasya Upanishad in simple language. The problem he faced was that despite translating the text word for word, he found no satisfaction because he could not grasp its 'internal secret' or profound hidden meaning. Feeling stuck, he took his doubt to Sai Baba in Shirdi. As mentioned in Chapter 20, Sai Baba's advice was intriguing and indirect. He told Das Ganu, "The resolution of this doubt of yours will be done by the maidservant at Kaka’s house When you return there," setting the stage for a future revelation.