I'm sorry about your chick.
Can you please post updated photos of her, her vent and her poop?
Is the vent still pasting over? Is she constipated?
Keep her warm, but not too hot.
I'd give her some plain fresh water in between all the remedies you are trying.
The airy crop is a concern. Any yeasty odor coming from her breath?
Do what you can to keep her hydrated and get nutrition into her.
Sometimes chicks fail to thrive no matter what we do.
Can you please post updated photos of her, her vent and her poop?
Is the vent still pasting over? Is she constipated?
Keep her warm, but not too hot.
I'd give her some plain fresh water in between all the remedies you are trying.
The airy crop is a concern. Any yeasty odor coming from her breath?
Do what you can to keep her hydrated and get nutrition into her.
Sometimes chicks fail to thrive no matter what we do.