This little girl ended up passing away after a few months. The necropsy never found anything and was a really awful experience. Before she passed away, she did start eating live rat fuzzies and then f/t rat fuzzies when left alone with them overnight. She also got evaluated as healthy a week before she died by the vet after finishing several weeks of antibiotics for an RI. With how low her weight was when we got her (>120g for a ~6 month old), she may just have never been healthy in the first place. I'll never really know. She was a real sweetheart and I miss her, but I don't know that I could have done anything else to save her.