HI
You should apply for discharge of sureties under Section 134 in The Indian Contract Act, 1872 in the local court.
arraying your father as Petitioner and Chit Fund Company as Creditor.
Since your father has paid all his liabilities, the chit fund company will file the No Objection certificate in the court and based on the No Objection certificate, the court will issue a discharge order in favour of your father.
Based on the discharge order, you can cancel the Demand Draft and subsequently encashed
It is a simple straight forward case and you should be able to get the DD's cancelled and subsequently encashed within 2 to 3 months from the date of filing of petition for discharge.
Hope this information is useful