Two-three mice/week is perfect for a ball at 800+ grams. Our mouse feeder 2500+ gram breeder girls will eat about 5/week after laying for a couple months, then I back em down to 2 once they have gained the weight back.

As far as the jaw seperation you saw, snakes lower mandibles are connected with a ligament which can separate quite a bit, not bone like most animals. They also don't "dislocate" their jaw like you normally hear, but they do have a very flexible skull which helps them "walk" their jaws over the prey until it is far enough down the hatch to pull it along with esophageal contractions. An amazing feeding adaptation that has allowed snakes to be so successful as a whole.

-Evan