I had the same issue with my bp, except with mice instead of rats. Had the girth for jumbo mice, and was definitely interested, but wouldn't touch them for a good month or so after I got them. He went on feeding strike/into shed for a month, and has happily taken two since he came out of shed. So you might try waiting an extra week between feedings and see if giving her hunger a little extra edge might encourage her to be less picky.

If that still doesn't work, I'd freeze them for a while and try offering one periodically or after a shed. She may just randomly change her mind and decide to take one.

She may not even need to eat a rat that big or that frequently though, but I will let people with more experience weigh in on that.