A good NDI lab could answer most questions abot this is in short order.
The metal holds the information whether this was a barrel obstruction, fired out of battery, overpressure round, or defective metal in the gun. Pieces of the cartridge, even tiny ones, provide valuable info.
When I was range officer on an Air Force base, a blown Model 870 was run through NDI and found to have blown from a handloaded round that was 60% over SAAMI pressure. The GI finally fessed up that he had slipped one of his "personal loads" into the weapon and caused the blowup. Until the NDI report showed it was not GI ammo, he had lied about using the illegal ammo and claimed the blowup was mysterious.