You don't have to believe it. They signed a two-way rematch clause. That's what It means. Either guy can invoke the rematch clause.
Hearn lying again saying he's never said there was a December 1st deadline. Just that he wants talks to start. Liar, liar, pants on fire: "We’re not willing to wait until December to see. A deal must be done in advance of that, subject to him winning. The offer that was made to us (previously by the Wilder camp) will look like absolute peanuts when this fight is made. "
It's laughable as nobody is saying Finkel has to agree to the latest deal, he just needs to actually have a discussion. The whole not prepared to even talk to after Dec 1st is a joke