I'm pretty sure that's just WCW Backstage Assault. That game came out in November 2000 and was developed by EA. The article lists the same release date and developer at the top. It also talks about how the game will entirely take place outside of a wrestling ring, which was exactly what Backstage Assault did. They probably just canned the PS2 release and went with the last-gen consoles (PS1 and N64). Besides, WCW wasn't doing too hot at the time, and this game wasn't receiving much favorable reviews.
Also, this would be a sequel to WCW Mayhem, but not any of the other AKI WCW wrestling games, because AKI stopped making them in 1998 and focused on WWF. AKI was working on WWF No Mercy at the time this article was being written (May 2000.)