How does a woman reclaim half her dowry if the dowry was the Qur'an and divorce occurred before consummation?

Scholars have differed on the permissibility of making the memorization of the Holy Quran a mahr (dowry) for a woman:

Those who prohibit it: The Hanafis, the Malikis (according to the well-known opinion), and one narration from Ahmad. Their argument is that private parts are not made permissible except by wealth, and because the memorization of the Quran should only be for the sake of Allah. Those who permit it: The Shafi’is, some Malikis (contrary to the well-known opinion), and one narration from Ahmad. Their argument is the Hadith of the Prophet (peace be upon him): "We have married her to you for what you have of the Quran."

According to those who permit it: If he divorces her before consummation and he had pledged to teach her himself: She is entitled to half of her mahr al-mithl (a dowry equivalent to that of women of her status), because teaching her becomes impossible after the divorce. If he pledged the teaching of the Quran as a debt (i.e., he did not stipulate that he would teach her himself): He must hire someone to teach her (a woman or a mahram). Additional details (according to the Shafi’is): If he separates from her before teaching and teaching becomes impossible (because she has become a stranger), a mahr al-mithl is due if he separates after consummation, or half of it if he separates before consummation. If he separates after teaching but before consummation, he may reclaim half of the teaching fee from her. If he pledged the teaching as a debt and separates before teaching, it does not become impossible; rather, he hires someone to teach her.