Also can you get a weight on a few of your birds.
These type of problems can be cause by being overweight.
Too many treats leads to overweightness very easily.
Sorry for your loss.
This isn't egg bound. Egg bound would be an actual egg stuck, I think.
This is probably infection.
Something like this:
https://www.merckvetmanual.com/poultry/disorders-of-the-reproductive-system/salpingitis-in-poultry