The main reason BP's dont eat is husbandry, that includes temps without a digital thermometer on hot and cool it's all guessing, not good!(if they get even a little cool many wont eat), security is stronger than hunger to most BP's (if the tanks to big or is glass with lots of activity or large hides they wont eat) and humidity 50%. Even if you have all that spot on perfect many BP's wont eat frozen or prekilled ever. Live is always going to get you your best feeding response.

Also if you are moving her to feed that may freak her out.

How old is she and how has she eaten in the past? Has she ever eaten for you? Many petsore people will say whatever you want to hear to make a sale "Yeah she'll eat frozen thawed".

Feeding frozen thawed is something established snakes maybe conditioned to eat. In my experience some will never switch and some finicky snakes will only eat mice or rats but not both. I would wait a week with husbandry perfect and try again with a live rat pup or weanling rat.