Has anyone had a family member go through a cancer fight with no insurance?

She's in Arkansas which doesn't subsidize so while they do have exchanges and that is an option it will probably be fiscally impossible. They can't deny you coverage, but they can sure charge through the nose for it and in states that are trying to kill the ACA like Arkansas they have done everything they can to reduce the effectiveness.

However, it is actually the first thing on my list to go through with her when I get there, so that may work.

I believe the subsidy is at the federal level, not the state level. Either way, yes, you'd be putting money up front for coverage and deductibles.