You may have no choice but to accept the spot in the class and put down a deposit. If you get into Haas at a later date, you can always pull your enrollment and eat the deposit. It sucks to lose the $$$ and it will make you feel a little bit guilty, but understand this: it's all part of the game. Schools put people on waitlists all the time and it is perfectly understood that you will get some "melt" from your admitted class as things stretch out. It's just the way things are.
So what I would do is wait a bit longer - maybe a week or so - and then lock up your spot with Davis. If you get into Haas, roll with it.
It's a simple solution, nothing genius about it, but it's really the only way to play it.
Hope that helps.
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