Why was Das Ganu struggling with his commentary on the Ishavasya Upanishad, and what solution did Sai Baba offer in Chapter 20?

In Chapter 20, we learn that Das Ganu was writing the 'Ishavasya-Bhavartha-Bodhini,' a commentary in simple language. His struggle was that even after a word-for-word translation, he felt he had missed the 'internal secret' or the deep, essential meaning of the Upanishad, and his mind found no joy in the work. The text highlights that understanding such profound scriptures is very difficult without a Guru's grace. When Das Ganu presented this problem to Sai Baba, Baba didn't give him a direct scholarly explanation. Instead, he mysteriously told Das Ganu, 'The resolution of this doubt of yours will be done by the maidservant at Kaka’s house.'