Going though the same problem, 2 of our snakes will only take live hopper mice, (The Hognose, and Banana Cali had always taken F/T before). The 3 year old Pueblan will only eat small pinkie rats and a small mouse, and now... our Taiwan is refusing large rats, guess we'll have to "downsize" him this winter.....
We offered smaller F/T prey to the Hog and the Cali for 2 months, and would not eat, before we had to resort to the live food. Best of luck!
A herper has to know his own limitations, (NOT!)