They are not ‘tapes’. It is digital, files a few minutes long, for each camera. Software operation is, often, run off Windows, with point and click, drag and copy functions.
Costco has a liability issue here, having called the police. Civil suit, millions.
For Costco, the messing up of the ‘tapes’ while unfortunate, could be a heads up move for a loyal lower management type. Basically, destroy anything that can be used against us. Wink-wink, nod nod.
Since the initial killing of Scott they have claimed problems with the video. They will either release damaged video that's no help or doctor them.