I had problems switching my BP to f/t. I finally found a way that worked, you should try it.

Thaw the rat (in a sandwich bag) in bucket of hot water till its mostly thawed. Dump the water out and fill the bucket again with hot water. Let it sit till its fully thawed. When its done, take the rat (still in the bag) and put it in your sink, let hot water drain onto its HEAD ONLY for about 3 minutes or so. After that, take it out of the bag and with a pair of tongs, drag the rat on the bottom of the tank like it's alive and moving. My BP goes for it a good 75-90% of the time!

I used to feed my BP live and she was just like yours, a non stop eater (I even fed her twice a week). When I switched to frozen, I tried every trick people told me and nothing ever worked. I randomly tried what I just explained to you and it seems to be working great! I've been feeding her like this for about 3 or 4 months now.

Good luck!