Droopy tail, posture, not defecating normally

[Hens_SWCT]

That's awesome! Her condition would have her slowly deteriorating over time, with untold thresholds of pain due to the chickens' code of "show no weakness" at any cost mentality. If she were my girl, I'd accept their offer of palliative care. Also, don't beat yourself up over your inability to pay for surgery as anesthesia is highly risky with birds and the doctors won't know what all organs have been affected by her illness or even if her condition would persist once they've removed the infected tissue. These factors make the surgery a craps shoot at best. Will they phone you when she's down to the bitter end so that you could go to her to make your final goodbyes? Would you want them to? With the proper pain medication would you be able to care for her and put her out of her suffering when the time comes?
I'll keep you and your feathered family in my prayers.

Unfortunately, she didn't make it through the night. She spent the evening under cover and resting, but her breathing seemed labored.

The fostering agreement was no contact / updates on condition once you hand them over. I'm assuming it's so people don't give them their pets, let them foot the bill, and then demand them back.