As there seems to be no way to register Notion for iOS as a product to get support for it, I'm asking this here.

I've got "Chorus" sounds installed, but when I select voices all i get in playback is piano. Aren't I supposed to get some approximation to the human voice (presumably in some kind of "oohs" and "aahs")? If so, how do I make it work?
If not, what is the function of the "chorus" sound and how do they work?

I'm using an iPad 3 with iOS 10.1.

And to forestall conversations I've seen in other posts:
[list=]1. Yes, I want "oohs" and "aahs"
2. Yes, I know there are limitations on voice sounds
3. Yes, I know some prefer to substitute other instruments.
4. Whether such substitutions sound better is a legitimate and perhaps interesting question, but that's not the question here.[/list]