Anytime you have a person who bumps their head, gets back up, and then has severe issues or dies like 6 hours later -- you have yourself an epidural hematoma from laceration to the middle MENINGEAL artery. (Goljan really emphasizes that you don't screw up and select middle cerebral.) You know it has to be an arterial laceration since the dura is tightly adhered to the skull's inner surface. Goljan referred to his experience with it as needing pliers to remove the dura from the skull; graphic, but it drives the point home. Tenting seen on CT is because the epidural hematoma gets stuck between the suture lines. When it manages to break past one of the suture lines, it is my understanding that then is when you get severe sequelae, like death or whatever.

To add on, a trauma to the skull => middle meningeal artery laceration => epidural hematoma. Epidural hematomas are known to cause transtentorial herniations and CN III palsy, which is what led to the patient's right pupil being dilated and poorly reactive (ipsilateral to the side of trauma).