Tire flank suddenly torn

Hello, yesterday my parents experienced an unpleasant event with the tire and fortunately it did not cause an accident. Tires at the front right suddenly broke during the ride. They were only two in VW Caddy (it was not loaded) and were not traveling so fast (about 70-80 kmh). The tyre pressure was tested last week and tires are not yet 2 years old and not much used (about 12000 km/year). And there was so far no known damage of these tires (when parking next to the curb edge etc.). But despite that, the tire flank is completely torn. Under these circumstances, I still don’t understand why this can happen? Can it be a defective tire, any manufacturing errors? Tomorrow we talk to the tyre trade, but I also wanted to ask you and get your opinions to understand why a tire can get so weirdly broken? Greetings Maxhttps://i.ebayimg.com/00/s/OTAwWDE2MDA=/z/EgMAAOSwOSdNNiL/$ _10.JPG