Both NYU and Columbia did their fee waivers on the LSAC system long before (apparently) they actually told anyone about the waivers. And the word on the street is that, for Columbia at least, it's just based on the LSAT score (I actually sent an adcomm at Columbia an email about this but she never responded to verify this information). SO, if you go ahead and start the app for Columbia or NYU and then act as if you are going to transmit the apps to the schools, it'll bring you to the pay page and you'll see there if they gave you a fee waiver or not. If there's nothing there, maybe that means you don't get one, maybe it means they haven't done it yet. But if it is there, I think that answers your question.
EDIT: You don't have to submit when you do this, you can go back and no one ever has to know that you peaked ahead.