All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
If your father, as is mentioned in the question, did neither throw the pebbles on the second day of Tashreeq, nor spend the night prior to it at Mina, then a sacrifice is due on him: i.e. a sheep is to be slaughtered in the Sanctuary and its flesh is to be distributed among the poor therein, because he did not throw the pebbles on the second day of Tashreeq. A mudd (750ml) of foodstuff is also due on him for the poor inhabitants of the Sanctuary because he did not spend the twelfth night of Thul-Hijjah at Mina. We hope that there would be no sin on him because he was ignorant of the Sharee'ah ruling.
Allaah Knows best.