If you are talking about a registered facility then there is probably little you can do regarding training records if they have gone missing. However you have a log book and that contains records of all flights. Aircraft Technical logs are required to be kept up to two years after the destruction of the aircraft therefore, all flights are traceable and the CAA will accept your log book for training received provided it is correctly entered.
Examination papers are issued to a custodian who is also a Ground Examiner, if the papers go missing the GE is not likely to be reauthorised.