"This time I took it to a local repair shop who said that the cables used to connect the hard drive were not the correct ones for that hard drive and this had caused the hard drive to burn out"
This is unmitigated rubbish - I would not trust anything else that this man says.
As for this time - who knows? - one thing that is virtually impossible is to tell how something strange happened, when there's no evidence to go on. Yes it could have been a virus - and it could have been a myriad other things.