lizards are cold blooded just like snakes they do not give off body heat. A ball python really does not rely on vision (Things that eat lizards has got to rely on vision at very least a little) to much to feed but rather it uses it's tongue and heat pits located around its mouth. It is far more likely it ate nothing or an occasional mouse, if it rained he had water.
Of course nothings impossible and some animals are just eccentric.