Back to the issue at hand... A rat pup is too large for a 57g BP. You need to either offer a small fuzzy, or a hopper mouse (LIVE). Also, the suggestion earlier about moving her to a smaller tub was a good one. You should also try putting her on aspen instead of paper towels - the "fluffiness" of the substrate seems to help them feel more secure. Get her eating for you a few times, and THEN you can worry about switching to F/T.
These are great suggestions. I also noticed you said you just leave the rat in her tub, have you tried a zombie dance? If so how long? Sometimes it takes a good amount of movement to get a strike...