It is a tough call. If you bought her ticket, she would also have 25K miles that you could use sometime. And she would earn miles on the paid ticket. Seems like that is easier than the transfer for $300.

Plus, if you bought her ticket, it costs $293 = $75, correct?

DL miles can be used for low level awards, but it is very tough.

But there is no reason at all to transfer miles for $300 then use your miles for her ticket. If that was what you were going to do, just spend the $300 on the revenue ticket and leave the miles in her account. Same net difference, except that she will now have a few thousand more miles. Even though you said SHE could care less about earning miles, you certainly seem to care about it. I would rather spend $300 (actually $293 - $75), have 26K miles and earn more miles on a revenue ticket than spend $300 and have 27K miles.