I know a great deal about hard drive infrastructure. There is no way to scratch one without not only removing it from the chassis but you must then cotort around the protective casing.
We were required by law to keep things depending on what they were any where from 1 week to perpetuity. Most of the Gov't stuff was a minimum of 7 years. My point is, I am not sure what sort of tech they are using. But I can virtually(pardon the pun), guarantee, there are backups, somewhere.