"I don't see how this should matter since she DID provide more than half of her support"

Well, it matters, because the IRS sets what matters. And, each credit, refund, qualification, is a different set of rules. Just like AGI vs MAGI is different.

Unemployment is Unearned income, but taxable. It's treated similar to investment income.

As you know, support and dependency and even custody, are each treated differently.

"All these resources are her own. I wish I could find where this question was asked. I think it was in regard to the education credits."

Student Loans are not income. And you might be thinking about EITC?