Personally I think feeding live with BPs is easier, less meal refusals than with f/t. But if you must its usually easier to switch them once they have become an established eater on live. Some BPs will switch no problem, some take a while. I always feed in their tank and never in a separate container. Some do the zombie dance, some don't, personally I don't think that it does anything. If you can get live I would spend the next couple months getting the snake on a consistent feeding schedule. Then you can try introducing f/t. Thaw the mouse, put under some kind of heat to get it well above room temp. Don't spook the snake, just gently move it around where the snake can see it. If it doesn't strike and constrict, you can leave the thawed rodent in the tub with the snake for a couple hours and leave it alone to eat.