Can't honestly say any of my snakes make much of a mess at all whether they are eating f/t, p/k or live. With f/t though if you've over heated the prey sometimes it gets umm a bit explosive or if the prey has been refrozen I've heard of it getting messy like that. Could just be the belly wall was thin and it popped from the pressure of her coil.
Some snakes like a lot of privacy to eat so you may need to just walk away and leave Ror with his prey so he can settle down and eat it. Other snakes need you to do the zombie mouse dance jiggle thing to promote a good strike and coil. Just don't leave the prey in so long it gets stinky and don't refreeze prey you've left in the tank for any significant time. Once you find the trick that gets him eating, stick with it faithfully as these snakes LOVE routine.
I have to say I have two out of my six balls that will not take anything but live. Doesn't bother me as I prefer to feed live and have tried it with all my snakes. If you prefer to feed f/t that's cool, you may just have to try a few things, be patient and consistent and also do a search here as there should be tons of threads on it.
Best of luck!
~~Jo~~