Sorry, to clarify one thing - is this for children in a spousal sponsorship or another type of app?
You should note one thing, although this comes up in family sponsorship (not rare even if not common), if it's an economic app, that's a different case. I don't follow those and so keep in mind that's the context of the answers you're hearing here. I don't know and can't say if it's treated differently for other types of apps - I don't offhand see why it would be treated very differently, but I just don't know.
At any rate, I think you've done what you could.