Could it be IB?

[LittleItalyFarm]

Hello, new member here but have been raising chickens for about three years now

I'm a little bit concerned about my flock (about 70ish), we had two girls die earlier in the summer to which we attributed to heat stress but my father buried them before I could take a proper look at them to rule out anything else (in school for pre-veterinary sciences) and this morning we found another one of our girls dead.
I did a quick check and found a seriously strange deformed egg stuck in her vent, she was three years old


Now as I was doing my evening check I found another girl in her nest box (the same age as the one that died) and decided to watch her just in case she was having trouble. She passed an egg alright, with no shell or membrane as all, just a goop of yolk and white. So I put my gloves on to check to make sure the egg didn't crack in her and the moment I put her upside down, clear mucus started coming out of her mouth.

I've got her outside now, seperated from the flock but her wings are very droopy, doesn't seem to want to move at all and as I was walking away she sneezed.

This seems to me like all signs pointing to Infectious Bronchitis but can anyone with more experience give me any clues to what might be going on?

Thanks!

PS, bringing to the vet is not an option, my father doesn't think a chicken is worth the money to get it looked at.

 

[LittleItalyFarm]

Edit:
additionally she feels very hot but that could just be the weather and her crop felt very full but spongy, i gave it a gentle press and what came out was a woosh of air (kind of like a burp?) and now it just feels like a normal chickens crop

Don't know if this helps!