I'm remembering that story now, thanks for reviewing it. I'm thinking will be needing to cut things up a bit smaller in the future. She acted fine the day before, but must not have been. Gulpy little chicken got greedy... How's THAT for a gluttony lesson. Glad I don't have a crop n gizzard, I'da checked out years ago! And, folks, that is the ONLY reason to keep an 'unchicken'... LOLI killed him right away and disposed of him further out in the woods. BUD had eaten from the gut pile as well but seemed no worse for wear, so I'm thinking that contents of the other roo's crop was too long and sinewy to advance into the proventriculus~or second crop~ and then into the gizzard, causing crop stasis and the resulting bacterial growth.
The large meat/tissue fragments seemed to be the culprit. My other birds had eaten chicken parts all morning, though they were soft organs like livers, fat, testicles, etc. and none of them had actually sampled from the gut pile except BUD...and I don't know that mere botulism could kill BUD, the unchicken.
I'd say those pieces might have been too big to advance from the crop to the second crop and into the gizzard and might have caused an infection there. The only place they will have grit is in the gizzard, so I'm thinking your large pieces of fish were the problem.