I have had the same problem sometimes feeding f/t. Usually happens when the rat is too warm or too wet. I do prefer live but no matter how careful you watch when the snake doesn't get a good hit it can get bit and scratched. It only takes one wrong hit for the rat to get a really good bite in. Even when watching with tongs in hand to stop from bitting. I do hate waisting when they refuse meals had one lil girl waist over 20 bucks in rats. I still will feed some live when they skip a meal or wont take that week. But man one good bite on a snake that I love and that also cost more then my truck just kills me lol. One other option you can try is p/k. Any just my experience, best of luck and hopefully no more exploders lol.
Sean