Just wanted to update - managed to track down a rat fuzzy finally. She had refused a live mouse the day before (she seemed to follow it, tried once to strike it, missed, and kind of gave up). Since I couldn't really keep the rat fuzzy alive to wait a week, I went ahead and left it in with her anyway.
Thankfully she ate it!
We weighed her after she refused the live mouse - she was only 119g. Weighed again the day after giving the rat fuzzy to make sure she didn't somehow bury it instead and she was up to 136g! (rat fuzzy was 17g). Going to get her a couple more meals and then work on switching her to f/t.