If she is refusing to eat larger mice/rats, try to feed her more often, I've had a ball python of mine eat 2 f/t rats within 2 hours of eachother, and the rats were just about as large as he should have been able to handle (girth of rat was the same girth as the snake)

Sometimes you'll have a ball who is a very picky eater, others will eat anything you put in front of it...
I also had a ball who refused to eat for the first 2 times I attempted to feed, so I starved him for 2 more weeks, after that he ate regularily for me, once a week

Everyone has their own methods

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