My wife is Cambodian and has Cambodian passport in her maiden name.

Last year, when she was a U.S. permanent resident (green card holder), I booked us on a flight from Cambodia to USA in her maiden name, so the booking would match the name on her passport. The flight is coming up in August. It is on EVA Airways, bought with Avianca Lifemiles.

The plan was that she would check in for the flight, show her Cambodian passport in her maiden name that matches name on the booking, show her U.S. green card in married name proving eligibility to enter USA, and show her marriage certificate reflecting legal name change proving that she is the green card holder. We've done this a few times before. Never denied boarding but the documents are scrutinized.

Her situation has changed now. She no longer has a green card. She got her U.S. citizenship and instead has a U.S. passport in her married name.

The ticket I bought a year ago is still in her maiden name.

My question is: Can she check in for the flight to the U.S. showing her Cambodian passport in her maiden name, which matches the booking name, and then when they ask "Where's your visa for the USA?" she says "I don't need one, I'm American, here's my U.S. passport," and then she shows her U.S. passport in married name and her marriage certificate proving the name change.

Will the airline accept that? Or will she be denied boarding because if she's using a U.S. passport to prove eligibility to enter the USA, then she must fly on that passport and the booking must match the name on that passport?

I will be asking EVA about this in advance, but sometimes different airline agents say different things, so I'm not confident about getting a definitive answer from a phone agent. I know that the safest thing to do is change her name on the ticket, but I'm not sure how easy that is since I booked it through Avianca.

Any advice or guidance anyone can give would be appreciated.