Is the husband sinful for not having children with his wife despite her desire to conceive and his not informing her of that, and is it permissible for the wife to ask for a divorce if the husband refuses to inform her?

The general principle is that procreation is a right of both spouses. However, it is permissible to refrain from it if there is fear for the children's religious upbringing.

A woman is not permitted to seek divorce except for a legitimate Shar'i (Islamic legal) reason, and a husband's refusal to procreate does not justify a request for divorce.

The mother of the aforementioned girl should fear Allah and strive to raise her according to Islam, inviting her to repent if she dislikes Islam, because disliking Islam is a sign of disbelief.

If the girl does not believe in the teachings of Islam, she is an apostate (murtadda) and cannot marry a Muslim unless she repents.

The mother should be gentle with her and try to save her, and persuade her to reside in a Muslim country.

What has been mentioned is evidence of the danger of residing in lands of disbelief for children.