1. The bank has the right to refuse to release the title deed of the property if the loan is not repaid. The contractual liability to repay the loan has now fastened to the legal heirs of your father. On the demise of the borrower his debts can be enforced against his legal heirs if there is succession of property in their favour.
2. Legally speaking, the dismissal of your father can be challenged by his legal heirs but the case will be very weak as your father who had personal knowledge of the circumstances in which he was dismissed will not be there to lead evidence in the court.