Shalom @Eggcessive@Akrnaf2 (Hi Benny) the OP said that her necropsy vet feels that it is a bacteria in the preliminary report. There were gram positive rods in the spleen and liver on gram stain. Apparently there are cultures pending. She has been treating for various problems.
I had guessed pasteurella which is a gram negative rod, so that was wrong.

Did the vet check in its culture if the bacteria is sensitive to any brand of antibiotics ? The OP could use penicillin or a pencilin derivate or a broad-spectrum antibiotics to try to cure them.