It more than likely had a cell phone or timer on it.
I tried a little research on the subject and found that the Pressure is used to confine the explosion until pressure builds up , making the eplosion much more powerful.
It has little to do with the pressure cooker itself exploding and more to do with the mechanics of building up pressure.
Yep. The cooker itself is ductile. It won’t break into very many pieces unless it is purposely “scored” to do so.