Re: Corrective Action for lost quality records
As an (Internal) auditor I would be concerned that this could happen to other records (i.e., system breakdown). You would have to convince me that the root cause has been eliminated, and that it will not happen again.
Without knowing the root cause or causes, I don't want to venture a guess as to corrective action.
One measure you can take to reduce the severity of the NC would be to have all persons involved in the project sign off (e.g. a memo) to say that all requirements related to the project were met, and an endorsement by the highest-ranking full-time person in the organization (e.g. CEO) AND a commitment to prevent it happening AGAIN.
the records of review and authorization which were in hardcopy forms are lost forever
If it happened again and I found it during a subsequent audit, it would suggest to me that both your Record control (ref. ISO 9001 4.2.4) and Corrective Action (ref. ISO 9001 8.5.2) are not effective.