Oven exploded after first use - refuse to replace

We purchased 10 Whirlpool ovens and installed them in a development 2 years ago. We have only just sold one of the homes and when the device was used for the first time, it exploded. As it was out of warranty they have refused to replace or fix it.

This is the second time one of their devices has failed, also after limited usage and they have refused to address the issue.

Herbie Hogendoorn is our contact who has been very happy to sell us the products but incredibly quick to pass the buck when issues arise.