In every direct report, they say it "shattered". The one who cut her tendons - it probably shattered while she was carrying it and dropped on the floor, sending out splinters, although I'm guessing a little there.
In another case, it shattered in the oven, and in the third, it shattered in the microwave.
And the one with serious injuries - she used the broiler, which they actually warn not to do.
There's another article that actually analyzes a bunch more cases. According to that one, 3/4 are temperatures under 375° F and more than half shattered in the oven.
Hmm, okay, the second report seems to indicate some actual explosions.
Three of them. And there was one case that ended in a gag order.
Honestly, it sounds like freak accidents to me, I mean, more people than that get food poisoning every year. Still, I guess the message is, be careful with your glass.