According to the text, why is the true reality of the Sadguru considered unknowable?

Chapter 22 portrays the Sadguru's true nature as profoundly incomprehensible. He is described as the formless one who is also the cause of form and illusion, a nature that is devoid of both being and non-being. The text emphasizes this inscrutability by stating that because of this, "the Vedas became silent." It further elaborates that even Shesha, the celestial serpent with countless mouths, does not know the Guru's true reality. This profound mystery leads the author to conclude that if such great authorities cannot grasp His essence, it is impossible for an ordinary person to truly know it, highlighting the Guru's supreme and transcendent state.