I'd do everything I can make her life comfortable and pain free from here on no what the ultimate outcome is.
No particulate beddings , just tiles (no glue no grout), no climbing, butadiene baths to help keep the wounds clean, antibiotics as prescribed, anti-inflamatories if prescribed, manuka honey on the infected areas and sterile dressings.
Plenty of high quality insect protein (the kind that is easy for her to catch and wont bite back - ie silkworms if you can get them).
It will likely take several months and several visits to the vet and a few surgeries to clean up the stumps perhaps but she's definitely worth giving her a chance.
I'm sure if her injuries heal up and she doesn't develop a systemic infection of some kind, she can lead a long and happy (even if disabled) life that's very rich ,even without rear feet.