Retired under suspension

There was a case of fraud in salary and accountant embezzled crores of rupees in his account and some other employees. My father was head clerk and he used to sign and order of release of fund was sanctioned by senior authority. The charge against my father is that he didnt done his job perfectly and there was grave negligence. He got suspended and in few months got retired. The official proceeding went for 4 years and later it was against my father and charge is negligence. the senior authority advised for his termination from job and seek advise from highest authority of state. No action yet has been taken. His name is not in FIR and all enquiries conducted tells that he has not taken any money. he filed a case saying that he signed the accounts by checking the total entry and sum mentioned on first page as it is not possible to check all details and further the fund gets released after senior authority recheck and sign. the court says that till proceeding is not finalised it cant take any decision. it is almost six years , after the incidence he got retired in six months. he is not getting full pension. he retired under suspension. how we can fight this case , he is 65 years and had been in tension for last 6 years and he is an innocent man.