Does Chapter 18 suggest that teachings from a Guru should be kept secret?

On the contrary, Chapter 18 strongly refutes the idea that a Guru's teachings should be kept secret. The text explicitly calls the notion that 'what the Guru has told one person should not be told to others' a 'merely imaginary and a meaningless fuss.' It argues that not only direct instructions but even spiritual insights received in dreams should be shared with everyone for their collective enlightenment. To support this, Chapter 18 provides the example of the sage Budhakaushika, who narrated the dream-vision of the Ram Raksha initiation to all. The chapter concludes this point by comparing the Guru to monsoon rain clouds, which shower the water of self-bliss lovingly upon all.