Hello, my name is***** and I have over 20 years of experience as a veterinarian. I am very sorry to hear that Kaweah has a subnormal body temperature, gas in the uterus and is septic.
I understand that you would prefer not to spay her, but I think that is the only good choice now, and even then she may not survive. Once we see a subnormal body temperature that tells us that our patient is truly critically ill, the body is shutting down, and we are in real danger of multiple system organ failure and death. Prognosis for patients with a subnormal body temperature is dramatically less than cats that can maintain a normal body temperature.
Sepsis means that not only the inflammatory products of the infection that lead to fever are circulating in the bloodstream, but that the infection itself has traveled via the bloodstream to other places in the body. This can lead to abscesses in filter organs like the brain, lungs, spleen, liver, kidneys and lymph nodes.
If she had a draining infection, wasn't feeling too poorly, and had a slight fever it might be possible to diurese her with large quantities of fluids, perhaps give prostaglandins to push the infection out of her uterus, and give intravenous antibiotics based on culture of the infection and have a hope of saving her reproductive tract. As she is now though I think the only thing left to battle for is her life.
I understand that this isn't what you are hoping to hear, but it is the truth.
Best of luck with your girl, please let me know if you have any further questions.