You probably should not leave a live rodent in there for more than ten minutes and hopefully you were monitoring it to be sure it didn't bite the snake since clearly the snake wasn't interested.

I suggest reading through this entire caresheet to be sure you have your husbandry perfect. If it isn't a husbandry issue then I suggest you leave her alone for at least one week to let her settle in. Get her two matching hides one for the cool side, one for the warm side. Offer her another live mouse after you've left her alone for one week. Read through my thread here, I listed the many things I did to get a stubborn eater to finally eat. You may want to try what I did. If that all does not work, you may want to try to find an ASF rat breeder near you. Some picky BPs readily accept ASFs.