As a practical matter, there is no way to compel the parents to give her this paperwork, if they are prepared to maintain the claim that the paperwork was lost. (That is, even if a court were to order them to turn it over, a defense to a court order is impossibility--i.e. they could not turn it over if it were lost. Since there is no independent way for the court to confirm whether the papers were or were not lost, such an order is essentially unenforceable if the parents will steadfastly maintain that the paperwork is gone.) Your son's girlfriend should contact the relevant state and federal agencies and look to obtain copies of the paperwork, the same as would any person who lost it.