If the battery didn't explode and the phone still works, it's obviously a case of a guy who dropped his phone , cracked the screen, and is pretending something else happened in hopes of a settlement or free phone.
Oh, and he doesn't know shit about how electronics works. It's pretty obvious that nothing exploded.
If he faked it, he not only lied about the cause of phone damage but also the head wound, so far as to get the phone bloody and go to the hospital. Maybe he was hurt otherwise, and decided to try and get a new phone out of it?