Orange ball python won't eat

[Duckboy]

We have an Orange Ghost Ball Python that is about six months old. He has only ever eaten frozen mice or rats. For the last several weeks he has not been interested in eating. He still has a healthy weight, behaves normally and looks good. I have been suggesting that we put a live mouse in there to see if the snake might be interested in it, but I am being told that because the snake has only eaten frozen food he wouldn't know how to deal with something running around the enclosure. This seems off to me. Don't snakes have instincts to eat live rodents? What should we do?