The word for "no"
The lesson description for "Dialogue I" reads in part:
The words HISlaH and ghobe'
HISlaH means "yes" and ghobe' means "no". These words are primarily used to answer yes/no questions. Later in the course, you will learn another word - Qo' - which is used to express refusal (as in "No, I won't!").
Note that unlike the English word "no", this word cannot be used as a determiner (as in "We have no bananas."), nor as an adverb ("I am no better."); it is strictly used as an exclamation.**
Does the second paragraph refer to ghobe', to Qo' or to both words?
Definitely to "ghobe'", but I'm pretty sure you can't use "Qo'" in those examples either.
What is said applies to both words, though I think the author was only meaning to apply it to ghobe', deferring discussion of Qo' to a later time. The second paragraph should be rewritten to make clearer what is being talked about.