ball pythons don't hibernate (also known as brumation).
his refusal could be due to any number of factors, the most likely being that he just decided to skip a meal today. however, I'd refrain from feeding a rat or mouse that's been defrosted, heated, and then cooled again. too many risks associated, the most mild of which is the feeder's internal walls being distressed to the point of rupture upon striking/constricting. it's one of the drawbacks of feeding f/t. I've had to throw out a good number of refused rats. some might argue otherwise, but unless you keep your own colony of feeder rats/mice which you euthanize and then immediately freeze, my opinion is that it's never wise to offer a feeder twice after it's been warmed up to feeding temperature.