Pale comb, lethargic barred Rock

[Wyorp Rock]

Ah I wish I had come back to this sooner. We opened her up and found rotten egg yolks and some broken shell so I’m assuming some kind of internal laying issue? Everyone else seems healthy (though one gal did lay a fairy egg today and we’re on edge after losing our first chicken).

Good for you for taking a look. Sounds like reproductive/internal laying.
When they have that going on in the abdomen, sadly there is nothing you can do except try to make them comfortable and put them out of their misery when the time comes.

A fairy egg can be a number of things - stress within the flock - she just lost a flock mate so the dynamics has changed. She may be getting ready to molt, etc.
I would just watch your girl, see that she is eating/drinking, offer oyster shells free choice. If she seems stressed, poultry vitamins for a couple of days might give her a boost.