The author of this article seems to be as ignorant as the chefs behind this incident.
Morels are known to be toxic until cooked. I’m surprised there was no explicit mention of this in the article.
In general, the boilerplate advice is to never consume raw mushrooms, even from species known to be edible, unless they are explicitly known to be edible raw. Button mushrooms are the only one I can think of. It’s likely other species are edible raw too, but it’s better not to gamble if it’s unproven.
People preparing or consuming wild foods should make sure to do the proper research. That is the only safe way to practice foraging. Very sad that people died because of this.