I think it depends, on whether they want an attraction with a spring like opening (around the time similar to Potter and Despicable Me) or that they could do more effort and have Fallon up by Late June/July.
It's possible, and that they can do it. It depends on how much effort they want to put in for something that can either be a.) a Flex-Venue show or b.) A Motion Simulator based off of one of Televisions longest running live shows.
And to add on, either one could be cheap, as Fallon is already a pre-existing attraction with a simple ride system that can be easily added. It would dirve screenz haters up the wazoo, and that the Flex-Venue replacement would be people complaining of it being a "Screen show replacing another screen show".