The three main elements of a copyright infringement cause of action are ownership of a valid copyright by the plaintiff, direct copying, and substantial similarity. None of those is reasonably in question here; the defendants played the entire video, knowing that it was Ethan's, for the express purpose of reducing his income from it, and stated that was why they were doing it, on video.
The primary defenses to copyright infringement are: fair use, independent creation, there being no reason to believe the content was a copyrighted work, the existence of a license, abandonment of the copyright, misuse of copyright, and statute of limitations. Independent creation, lack of reason to believe, abandonment, and statute of limitations are obviously off the table. Hasan could claim license if Ethan sued him, since Ethan invited him to respond to the video, and Ethan has admitted this, but it's a long shot for the others to claim it without an express statement from Ethan to support it. Fair use would normally be the primary defense, but the defendants' public statements that their purpose was to deny Ethan views again renders this non-plausible. Misuse might be another avenue that they could try, but I don't think it fits; he's not trying to gain an unfair advantage beyond the scope of of copyright protection, he's simply enforcing the normal rights rather than trying to create a monopoly or restrict competition.
In short, I think he has a good chance of prevailing on the merits and defeating an anti-SLAPP motion.
I cannot stress enough how retarded these women are for making the most damning admission possible, on camera, with the proof of direct copying playing in the background.