Faulty Explora

After a power outage my EXPLORA would no longer work, so I took it in to the Service Centre in Goodwood and after it was checked by a technician in the back office was advised the hard drive was damaged which was most probably caused by the power outage. I was immediately offered an exchange at a cost of R510.00, I declined and contacted my insurance who advised I was covered and they would cover the cost on receipt of a damage report, on requesting this from Mutichoice I was advised that they can't give me a letter saying what the fault is. Now I ask how can they tell you what's wrong and offer a replacement at R510 yet can't give you a letter to say what's wrong??? Without this letter my insurance will not pay-out.