1. Whether Fox has any interest in making the movies is irrelevant if the contract prohibits Jordan from doing it. Plus, I doubt they're making any more Fantastic Four films with this cast. If Fox makes more, they'll re-cast.
What I'm saying is that by the time Chris Evans signed on to be Captain America, RotSS was three years in the past with no movement or even mention of a sequel. If Michael B. Jordan were cast within the next few months, it'd be quite a difference. Fox only just went back on their promise to make a sequel, they could easily put on in the works if they wanted to. Also, Marvel and Fox aren't on the best of terms. They could put a sequel into development just out of spite.
And I don't think they'd recast. They'd give it another go and reboot the time after that. Sequels get less hate than reboots, especially so soon.
Ok, I'll remove my tinfoil hat now.