Is the Hajj valid if a man has intercourse with his wife after Tawaf Al-Ifadah and before sacrificing the animal offering on the tenth day of Dhul-Hijjah? And what must he do?

If the pilgrim stones Jamrat al-Aqaba and shaves or shortens his hair, he is released from all prohibitions of ihram except women. If he performs Tawaf al-Ifadah and Sa'i (if Sa'i is required of him), then he has achieved the second release, by which all prohibitions of ihram, including women, become permissible for him. Sacrificing the Hady has no connection to release (from ihram) nor is it dependent upon it.