What challenge did Das Ganu face while working on the Ishavasya Upanishad, and what was Sai Baba's initial advice to him in Chapter 20?

Chapter 20 recounts the story of Das Ganu, who undertook the task of creating a commentary on the Ishavasya Upanishad in simple language, called the "Ishavasya-Bhavartha-Bodhini." Although he translated it word for word, he found no joy because he could not grasp the internal secret and deep meanings of the scripture. When this doubt arose, he went to Shirdi and approached Sai Baba. Baba's cryptic advice was that the resolution for his doubt would be provided by the maidservant at Kaka’s house upon his return there, setting the stage for a future revelation.