Oh so sorry for your loss. Would you like to get a necropsy performed by your state vet? Her body may be kept refrigerated (not frozen) until you can contact the state poultry lab. Georgia has quite a few labs in this link: http://www.metzerfarms.com/PoultryLabs.cfm
Since I am NPIP certified, they will do the necropsy for free. I will keep her cold (not frozen) and drop her off tomorrow morning. :'( She and her sister were our last addition to the flock (other hen a rescue hen). They were hand raised and their names were Sam and Ella (say it fast). Thankfully Ella hasn't paid attention that she hasn't been around.
We are always learning new things here especially when others share their necropsy reports. So, if you can, post them here when you get them back. I had salmon faverolles—Sam and Samonella. Sam lives on.
The necropsy report came back: Bird had infected ovary and bacterial peritonitis. So I am assuming that the broken egg inside of her cause the infection.
I doubt if the broken egg she had recently caused the peritonitis. She probably had it for awhile. They can sometimes get an oviduct infection from bacteria entering upward from the vent. E.coli is an opportunistic bacteria , pretty much everywhere in coops, and sometimes other bacteria may be around. They can suffer with an oviduct infection and peritonitis for weeks or months. But this last episode probably just did her in.
Thank you for sharing the results, and glad that it was not something that would affect your others.