Maybe, but the crew deleted all the cockpit voice recorder data because…?
.. because that has been standard Industrial pilot practice for donkeys' years. I would have been astounded had they NOT wiped the record !
(Caveat - I am a bit removed from practical pulling and pushing these days so my comments may only apply to days of yore ? Certainly, in my airline days it was a pretty standard process as the intention was that the CVR only be read in the event of dead pilots. Many crews made it a routine practice to wipe the CVR at the end of every sector. As you might be aware, not all airline management groups are of high moral integrity seeking only the truth of any matter. The only instances I can recall where this was not the practice was where the captain saw fit to use the CVR as evidence for some problem or another and required the unit to be pulled post flight.)