As andyo5, said in post #28, "I see a crack in the frame which appears to have originated at a corner of the trigger cutout. I didn't see a 'blow up'. Did I miss something?"
This from your Original Post!
"This M&P was a lemon! It jammed from day one, never functioned properly. was told to clean and oil it good as it could have dried out on display at the store. Had my gunsmith go through it, clean and oil it and for about 2 magazines it worked. This is with FACTORY ammo! Finally when my grandson was firing it, the damn thing blew up in his face, the slide flew back and hit a friend of his in the forehead cutting him, and parts went everywhere."
No evidence in your pictures of a catastrophic Blow-up and slide disengagement with parts going everywhere. All I see is a crack in the polymer frame behind the trigger cutout. You did not post pictures of the frame slide rails or any other parts of the pistol that came apart.
You made no mention of "shooting reloads" in your original post. I still have reservations as to what actually took place!
mb