Is it permissible for a pilgrim performing Hajj Ifrad to stay overnight in Mecca after the Tawaf Al-Qudum on the seventh day, then go to Mina on the morning or evening of the Day of Tarwiyah?

There is no harm for the Hajj al-Mufrad (one performing Hajj only) if, after performing Tawaf al-Qudum (circumambulation of arrival), he remains in Mecca and stays there while still in the state of ihram, as long as he avoids the prohibitions of ihram, until he departs for Mina on the Day of Tarwiyah. This is the Sunnah and the practice of the Muslims.