Here's why:
* Camazotz is a terrifying place: It's a planet ruled by a malevolent being called IT, where everyone looks and acts the same, devoid of individuality and free thought.
* The journey is dangerous: Meg, Charles Wallace, and Calvin face numerous challenges and threats on their way to Camazotz, including the Black Thing, the "It" that tries to control Charles Wallace's mind, and the fear and confusion that comes with navigating the unknown.
* The stakes are high: They are on a mission to rescue Meg's father, Mr. Murry, who has been imprisoned on Camazotz.
While "dreaded it" isn't explicitly stated, the fear and apprehension surrounding the journey to Camazotz are evident throughout the book.