I say, and with God's help: His wiping is invalid; because the duration of wiping starts from the beginning of the fainting; and fainting nullifies the ablution, so does wiping. Refer to: Tanweer al-Absar, Al-Durr al-Mukhtar, and Rad al-Mukhtar 1: 185, and Al-Hadiyya al-Ala'iyya p. 40, and God knows best.