Hi, I had an old multibit wallet (2014) in an old PC which had a hard drive failure. Sadly my mother brought the PC to repair and she didn't know that the BTC was there. The people who repaired gave her an external drive with some info.. and put a "new" harddrive ( i don't know if this is true ) ...
If they replaced a dead drive with a new one, the dead drive probably went in the bin (and so did your wallet)?
In the end you are telling us the PC had a drive failure so if the drive failed it is normal for the repair-shop to replace the hdd.
But then I'm not sure why they gave your mother an external drive "with some info" ? ...