-- Vince McMahon is reportedly against the idea of having Braun Strowman face Brock Lesnar again at the Royal Rumble in January. For one, the match has already happened and Lesnar won clean. Second, Strowman is being readied for a match against Triple H and isn't going to be losing while Lesnar isn't going to have anyone kick out of his F5 until Roman Reigns does it at WrestleMania.
-- No matter what is booked, Brock Lesnar is scheduled to be appearing at the Royal Rumble in some capacity but it's possible he may not be defending his title. With Finn Balor seemingly out and Braun Strowman not a realistic possibility, the only wrestlers left are guys like Bray Wyatt, Elias, Jason Jordan - who are actually in worse position than Balor.
-- Samoa Joe is a possibility and would likely be the best alternative as it could be a singles match for the title.
Source: Wrestling Observer Newsletter. Subscription information & prices available at f4wonline.com