1. If the matric certificate had an inaccurate date of birth then you should never have used it. You are liable to be prosecuted and punished with imprisonment for 2 years for furnishing inaccurate details.
2. You should be thankful to the RPO that it has merely asked you for a court order to incorporate your correct date of birth in the passport and has not prosecuted you.
3. To obtain the necessary orders from the court you are required to file a lawsuit.