Seriously? If her phone got hot in an elevator, she shouldn't have put it in her purse? What else should she have done with it? Was she supposed to anticipate that it was about to catch fire?
Phones are designed to be kept in bags, pockets, etc. Or on car dashboards in direct sunlight for hours, etc.
It's one thing to say (correctly) that we don't yet know for sure what happened. It's another to make up preposterous, victim-blaming criticisms just because you like the product and hope it's not defective.
Unless someone drives a nail through the phone, runs over it with a car, or inflicts similar abuse, it's Samsung's fault if it catches fire.