You may as well approach BOARD which gave you those certificates asking for duplicates of it. Cheap and best method.
Proving that you gave it to her or you left it in her custody, she telling she does not have, you telling she has it, you proving that she has it is all such a waste of time and money. Let the court proceedings take its own time, but if you are in urgency to have those certificates and documents, you can get duplicate copies of it.
Anyways it is better to take MCD and part ways instead of wasting time in court halls which none of the above so called experts have suggested.