If she has the score and you have the income, she will get approved. I haven't had a real job in years, but with my near perfect credit score and my husband's income, anyone will give me a card.
With a 2% service fee, it will only make sense to use cards if you are getting excellent sign up bonuses. If you have other spending to put on the cards, it might still make sense to use cash for the tuition and use the sign up bonuses on your normal spend.
I have had the worst luck with Capital One customer service, but their Venture card makes it easy to transfer rewards between husband and wife and easy to pay off any travel expenses with the points.
Also watch out that the annual fee isn't eating up your bonus.