Congrats on the admits!
Best thing to do is to call up Vanderbilt and talk to them. It's going to be done on a case by case basis, so just be friendly and direct about it (i.e. people want to help those they like). In other words, ask (don't demand).
As for both schools, it sounds like you know the differences between the schools more than I do; trust your judgment on this one. Whether you choose the money over what you feel is the better school is really a personal decision; if it's hard to decide, it's because it can go either way (and that you'll probably be fine either way). You just need to make a choice. Good luck
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