So now you know that she's prohibited from accepting a gift over $25, yet you are still going to offer her a trip to WDW? I see no purpose, except your own gratification, in going ahead with the gift.
You are putting her in a very uncomfortable position. She will jeopardize her career if she even considers accepting. Therefore, she'll probably refuse but very likely feel awkward with you from now on.
If you really are just grateful and generous then ask her what equipment you might donate to make her job easier. Then make the donation through the school.
I agree. I don't see how it could possibly be seen as generous to do something that you've been told, even by her own employer, is inappropriate and not allowed. You could cost her her career, or at the very least, her reputation.
As a substitute teacher, a parent once wrote me a glowing review. She sent it to me and a copy to the prinicipal. Guess who never worked at that school again? Seriously, those kinds of things are looked upon with suspect, even if the intentions were good. Even the fact that this professional had a conversation with you about her inability to afford WDW could be seen as inappropriate by some. It's easy for me to see how it could have come up, but very easy for someone to misinterpret as well. Even Ellen, Oprah, etc. are not giving these things to people they are professionally involved with.