Honestly, for the cost why not just sell the rights to Disney?
I doubt Disney wants to pay for it. For all the non-Disney rights Marvel properties (FF4, Spiderman, X-men, etc.) it is a use or lose it situation. Fox, Sony, et al. have to pay the money to put out something to keep the rights, otherwise it goes back to Disney/Marvel. If a new rushed FF4 fails, then it is quite possible Fox gives up on it and Disney gets it back for nothing as happened with Daredevil, Ghostrider, Blade, and the Punisher.