So may have lost their systems, hard drives etc and lost their coins for good, so you're one of the lucky ones, losing all those information will be tantamount to losing quite a whole lot of money, even though a the initial stage it was worth nothing, but it's pay for being their from the beginning and working on the network.
Just like the CEO of an exchange where he died early this month and he is the one who controls private key so i think it will be hard for them to recover it. Youre lucky to find your hard drive, and because of this i think i should backed up my wallet now so my family will still be able to recover it. We should always protect and backed up our wallet at all times.