contrary, I'm so sorry that on top of the nightmare that is your daughter's disorder, you have to put up with people speculating about what you did to cause it. The answer, of course, is "nothing".
This is another reason why the constant armchair diagnosis of something as serious as NPD really irritates me. To the point where we even have neat little abbreviations for it ("narcs"). Genuine NPD is too rare to justify having its own everyday slang term in common parlance.
I couldn't count how many times I've seen people, here and elsewhere, online and in real life, ask "Is my ex/mother/sister in law a narcissist?" The answer is always, "Most likely not. We don't fucking know, ask a psychologist who's got more than a highly partisan internet account to go on!"
It's as if people WANT their nasty relatives or partners to have NPD and honestly I am fucked if I know why. The only answer I can think of, as I said earlier, is that people somehow feel they don't have a right to be as damaged or upset by this person as they are, unless this person has some sort of serious disorder. Which also doesn't make sense, because if someone is really that clinically ill or disordered, then arguably they're not responsible for what they do and they need help.
And yes, all these "narcissists" probably do display similar tendencies, for the same reason that so many cheating partners follow "the script". It's called psychology and psychiatry. People are not robots and are all different, but as a general rule most of us respond similarly to certain stimuli such as authority, incentive, and getting caught in an affair. It doesn't mean we're all disordered, it means we're humans and for the most part share some similar wiring.
Honestly, the only constructive thing you can do in these situations is to try to look at your own mindset and try to see why you didn't see or didn't heed these red flags, and look out to avoid them in the future. I hear the Freedom Programme is good for this.