A lot of extra work that probably won't work since her blood sugar will still be a mess. I hate to be the bearer of bad news, but it's next to impossible to out train a titty diet because everyone who told people it was a simple matter of calories in minus calories out was either misinformed or an idiot.
And Pike, if you find it difficult to cut back on pizza and pop, then you can try cutting back gradually. Plan your days where you're going to have the stuff, like maybe eat really well for 3 days, then the other 4 have a cheat meal and gradually try to dial it back. I tend to lack the willpower for that so it's never worked for me but it's worth a shot. And is there diet mountain dew? I can't recall ever seeing such a thing but I'm rarely in the pop aisle. If there is, try switching to that and then gradually cutting it out. Diet pop isn't exactly ideal, but at least it can help you start getting away from crazy blood sugar spikes and crashes which is what's going to help burn fat and lose weight in the end.