I have the same problem but in reverse. My five year old Corn was raised on F/T mice then F/T rats. Not long ago he started refusing the rats. I had three F/T large mice in the freezer. He will still eat F/T mice but not rats. Live small rats cost a bit over two dollars. Three live mice cost twice as much. So he wins. I know about the risks. But he wants live rats so he gets live rats.
I have to mention that I was flamed here for feeding him live rats. :uhoh:
I was also bashed for not euthanizing feeders acording to the rules of some forum members. :bowdown:
One even called me a troll. :laugh01:
Good luck on getting your snakes to adapt to frozen food. I tried everything. After he refused F/T for over a month, that's right, he didn't eat for over a month, I gave in. It's a pain buying a feeder each week.