What do you think Wilder will do next to try to salvage his career now?
The only way he can fight for the heavyweight titles now is by becoming a mandatory challenger and that can only happen if he wins a couple of comeback fights.
Does Wilder even still have it in him to retain a high level of dedication now after Fury showed him over 3 fights exactly how inept he was when confronted with a superior colossal fighting machine (in Fury).
The simplest and most obvious scenario that comes to my mind is to fight any other boxer who is high enough in the ranking and of course to win him by knockout (as before he met Fury). After that, take a look at the result of the Joshua - Usyk 2 duel and if he succeeds in agreeing, then fight the loser (since the winner will apparently go to the fight with Fury). If by this moment Fury remains undefeated and Wilder shows good boxing and previous results (knockout victories), then I would not be surprised if he can reach an agreement on the Wilder - Fury 4 fight.