Is my university student daughter able to claim the standard deduction

My wife and I lived in the USA for 13 years and had green cards which we gave up when we moved back to Canada so we do not file with irs.

Our daughter is 20 and dual USA Canada citizen as she was born in USA. She files with IRS. And I do her tax return.

In 2025 tax year she was in school in Canada. 98 percent of her university expenses were paid for by proceeds from her 529 that is in my brothers name now as owner (he lives in USA). The rest she paid herself. My wife and I did not pay for anything out of our bank account. Is she considered a dependant of ours? ChatGPT is telling me if she is a dependant she doesn’t get to claim std deduction. It says she is a dependant because 529 was funded by us. If she uses the formula for the deduction she would get as a dependent (it tells me she cannot claim standard deduction) she would have to pay a few hundred dollars in tax versus standard deduction there would be no tax due.

Can I claim the standard deduction or do I need to use the formula which results in a reduced deduction for her?

Thanks!