Yeah, this is pretty upsetting to see. I hope something can be done swiftly--as it appears some people are buying the games from him already and he's potentially profiting from this.
I don't know if you can report accounts directly, but there's a report link at the bottom of each game page. It might be worth doing so just to notify itch.io about his account in general.
I've attempted to notify some of the devs listed in those games, too since I imagine it's better for itch.io to hear from the devs directly--but I have no idea if I've reached them or not since some of them are really difficult to get in touch with. But hopefully it can be resolved swiftly!