Even if the numbers are accurate there are lots of variables. For example the steel could have been defective from the steel factory. It may have been improperly heated/heat treated.

Even if the slap round was way overloaded with powder something must have caused a barrel obstruction right? Otherwise the pressure would have taken the easy way out the barrel

I think he went over that there was no barrel obstruction. The last slap round that was shot was found stuck inside the fire hydrant.  And the fireball from that round that was at the end of the barrel was bigger than normal (signs of a hotter load).  However, there was no mention of the ears that were ripped off.  He is sending the rifle back to Sebu and they will investigate.  Sebu made no mention either of the strength of the ears, just the threads and the amount of pressure it would take to blow off the cap.

I think he went over that there was no barrel obstruction. The last slap round that was shot was found stuck inside the fire hydrant.  And the fireball from that round that was at the end of the barrel was bigger than normal (signs of a hotter load).  However, there was no mention of the ears that were ripped off.  He is sending the rifle back to Sebu and they will investigate.  Sebu made no mention either of the strength of the ears, just the threads and the amount of pressure it would take to blow off the cap.

If it gets litigated then all of that would come up. Serbu would try to blame the metal manufacturer and the bullet. The bullet maker would try to blame the gun, the metal manufacturer would blame the gun, etc. They would need to prove who was negligent and how much so.