If the negotiations succeed, Belz would benefit by possibly increasing the government support of their schools to up to 100%. As a private school now they get only 55% max of government support, and they always claim much less in reality. It seems they are in a bit of a financial bind and recent fundraising efforts have fallen short, along with efforts to increase support from Chinuch Atzmai also failing.

As part of the MaMaCh system Belz would commit to implementing full secular studies into their school systems with the bagrut testing as well. They would focus on bagrut in the fields of mathematics, English language and Hebrew language. the government would likely have to agree on no external supervision and inspections and would instead limit the supervision to reviewing the semi-annual testing. The level of support would also depend on the level of success in the testing, as that would indicate that they are actually teaching and studying the material and taking it seriously.

This is a major shift. The institutional Haredi community has vehemently opposed the MaMaCh system. Even if it does not work out in the end, though right now it looks like it is nearly a done deal, the fact that they have been negotiating, and seriously negotiating, is itself a big deal and a monumental shift in Haredi society. I dont know if it will lead to other communities adjusting attitudes as well and consider joining the MaMaCh system, or at least not opposing it as strongly they have until now, but a major community like Belz joining it is definitely going to go a long way to kashering it in the minds of many.

The Haredi community always claimed, especially about the educational system, that they cannot be bought for money - they will never change just for increased budgets. It looks like that is just a myth.