Generally, applicants can run each school’s NPC, and if it looks affordable it is 100% acceptable to apply ED. If the FA offer doesn’t match the NPC results, making the school unaffordable, the ED agreement can be broken. I am not going to address each of the comments made in the post above, but suffice it to say that the Amherst situation isn’t happening anymore due to the ongoing DOJ investigation.
The rub for OP is that NPCs often aren’t accurate for international students…there’s currency conversion issues, tax law/definition issues, and more. With that said, OP could try to run the NPCs by converting currency and making their best judgement as to what their family’s corresponding AGI is. If OP’s parents are divorced, they need to include all income and assets of both parents (and new spouses, as appropriate). If NPCs don’t work for OP, it is still acceptable that they apply ED.
IMO OP’s larger issue is a relatively low GPA (many students who have faced significant challenges don’t see such a dramatic GPA drop) and high level of need, as all but five US schools are need aware for internationals.