Can you explain the problem Das Ganu was facing with the Ishavasya Upanishad and what Sai Baba told him to do?

Chapter 20 explains that Das Ganu was composing a commentary on the Ishavasya Upanishad, titled 'Ishavasya-Bhavartha-Bodhini', to make its teachings accessible to those unfamiliar with Sanskrit. While he managed a word-for-word translation into simple Prakrit, he became distressed because he could not grasp the deep, internal meaning of the scripture, and his mind found no joy in the work. When he took this doubt to Sai Baba in Shirdi, Baba gave him a cryptic instruction. As recounted in Chapter 20, Baba told him, "The resolution of this doubt of yours will be done by the maidservant at Kaka’s house when you return there."