Even if they were all in the same building, nothing short of someone running around with a ball peen hammer physically destroying the drives would explain this.
The Deskstart hard drive failures were controller board faults. The data written to the disk would still be recoverable.
Again, aside from physically opening the drive enclosure and hammering the disks, there’s no way the data was lost.
I haven't seen any information yet on what happened to the other 20 computers that crashed or exactly when they crashed. Until more info is provided, we can only speculate. Some or all the crashes might have been do to viruses. I would expect more info to be forthcoming.
Regardless of data recovery methods, most people like myself find it unconceivable that senior staff wouldn't be backed up or at least have a file server directory that is...