It's okay. He can still fix it. He just needs to message Ethan and tell him to please go on all his social media accounts and announce that he is actually willing to fight Hasan for CC3, then message Hasan and get him to agree to fight Ethan somehow. Offer him the world, and get Ethan to play along if Hasan's demands include something from him. Hype it up so much that Hasan would at least think twice before dropping out, and then, on the day of the fight, when Hasan is stepping into the ring, Ethan is nowhere to be found. Instead, Sam Hyde emerges. Two things can happen now: either Hasan fights Sam for pride's sake and we all win, except Hasan, or he runs away while the cameras are rolling, ensuring a lifetime of mockery. No matter the outcome, we win. And if Hasan never accepts to fight, it would at least drive a lot of trolls and insistent fans his way, which would make him tardrage a little, and it would be a nice gesture for Ethan after this fuckup of a tweet.
This all hinges on Ian not being retarded, Hasan losing several IQ points, even in the scenario where he refuses to fight altogether, and Ethan being willing to joke around with this topic, none of which is possible. Sammy would do it though.
Edit: If Hasan runs away, Ian steps into the ring, but he doesn't fight Sam. Instead, they hug and kiss. It's beautiful. Everyone cries and cheers.