I am glad that you are ok other than that finger contusion.
As others have said, the most simple explanation is probably the correct explanation: probably a double charge of a very quick-burning powder.
I don't think a "bulge buster" or "pass through" die will fix that brass.
Thank you very much for posting these photos. A reality check now and then is good to see. Sorry about your gun!
"There is nothing like looking, if you want to find something." Thorin Oakenshield