1. A case of cheating, misrepresentation, fraud and forgery can be lodged against them U/s.420, 408,468 & 120B of IPC against the persons. Also the employees can be subjected to Departmental Disciplinary Action.
2. Pension amount given to the deceased wife cannot be termed as illegal.
3. Inform the State Lokayuktha about the big properties the employees are owning.
4. Inform the Income Tax and the Commercial Tax department of the tax evasion and the owning of big business by these two Central Govt. employees.
5. Use RTI and find out how Mr.Nagrajun rejoined the duties even though he was absent for more than a year and what was the action taken on him and how his absence was treated by the department. Was he paid the salary for the absented period or the leave was on leave without pay.
6. You can take action as per the details in Sl.No.1 of this answer and obtain the necessary details about the two employees by using RTI.