Where's the money coming from? The NXT fans who are already paying WWE so that they can watch NXT lol?
But Survivor Series isn't the place for anything like this. It's already a joke due to the Raw vs Smackdown fakeness, throwing NXT into that mess just gets them mucky too. You're far better off doing it alone later.
You can make a good story from an NXT invasion for sure, but it's not going to be anything as big as the WCW one back forever ago so it's not going to be a big money anything. The best invasion to do right now would be getting Omega, Cody et al. But that's not really a possibility unless they want to play ball.
As for how I'd do it, I'd have HHH leading it and NXT must win. At the end of it all, the NXT champion pins the WWE Champion clean with control of the company on the line, and HHH (legit) takes control of WWE. It's Vince's retirement storyline.
And because that's my ideal with it, I don't think it's something you throw away just because it would be fun. It's not something you can do multiple times and have the same effect. It'll be a good card, so you should save it for later.