His financial obligation ends either when you turn 22 or at 10 years from your landing date, whichever comes first. Sounds like you turning 22 will be what ends his financial obligation.
All that means is that he promised the government that he would provide for your basic needs, and if you have to go any kind of government assistance (because he is not meeting that obligation), then he may have to pay back the government for whatever government assistance you got. That's it. Theres nothing he can hold over you