Yup it's quite a boon for them, though the story also said their total revenue is almost 1 billion, so it's not just that. And as you note, while this is an extreme and one-off exception, so many other things big-market teams do also evade revenue-formulas that makes sharing and a cap completely skewed. I'm sure the Philles' income from owning part of NBCSN doesn't count. Nor will their involvement in re-developing the sports complex.
The financing mechanisms do sound a little dicey. When it all shakes out with the insurance companies and the way some of that money helped fund it all, they might have to take a few steps. Maybe that's why the Dodgers welcome a cap too!
Walter's personal wealth is still estimate to be much closer to Steve Cohen than Middleton; only question is how much of that is tied up in these deals.