I read something about Das Ganu and the Ishavasya Upanishad. What was the problem he was facing, and what did Sai Baba tell him to do about it?

According to Chapter 20, Das Ganu was working on a commentary called the "Ishavasya-Bhavartha-Bodhini," which aimed to explain the Ishavasya Upanishad in simple Prakrit language. However, he encountered a doubt and could not grasp the internal secret of the Upanishad, which left him without joy in his work. When he took this doubt to Sai Baba in Shirdi, Baba told him that the resolution would come from an unexpected source: the maidservant at Kaka’s house, where Das Ganu was to return.