I have not heard of the Neverland Cafe - either currently open or closed.
There is the Neverland Club, but that is a place where kids can hang out without their parents for an evening.
So I am giving this a couple of guesses, but if anyone knows about where this really is, I would love to find out.
Bongos Cuban Cafe - they do have music acts there, but I haven't heard about a stage rising out of the floor.
The Tomorrowland Stage - bands play there, but it isn't a cafe, and again, I'm not sure about a rising stage.
Cosmic Ray's Starlight Cafe (in Tomorrowland) might be the place - I think that (I can't remember his name!) the lounge singer moves up and down on a section of the stage.
Hope there is something in here that might be helpful!
Hope your sister has a wonderful time at the greatest place in the world!