@Lambie A problem on this site is the insistence on the use of a niche terminology by a few people that's at odds with the majority of what others use. It's somewhat akin to Lewis Carroll's comment about how when they use a word they can have it mean what they want. Which is perfectly true. But it doesn't help with communication among the greater number of people who have it mean something else—rather, it generates confusion when trying to have a dialogue.

Her classification is not wrong. Take that on board once and for all. They are not utterances; they are the basic clause types that align with the various speech acts. It's not a matter of "not agreeing with every word", but one of having a basic knowledge of English grammar, which at least the OP has. Further, any competent grammarian would know about subordinate interrogatives (embedded questions). It's basic grammar, not rocket science. Go learn it.

@JasonBassford This is no niche terminology. See for example The Cambridge Grammar of the English Language by Huddleston et al. (2002), or A Comprehensive Grammar of the English Language by Quirk et al. (1985) – the two most prominent comprehensive descriptive grammars that I know of.