WWF

Zachary Guthrie mentions Sindbad being called up to it when Sindbad mentions "grappling".

This is likely referring to the "World Wrestling Federation" run by Capitol Wrestling Corporation (1979 to 1982) then Titan Sports (1982 to 1998) then "World Wrestling Federation, Inc." (1998-1999) then "World Wrestling Federation Entertainment, Inc" (1999-2002).

From 2002-2011 it was called "World Wrestling Entertainment" and "WWE" from 2011+

This implies Zach came from a pre-2002 version of Earth. It's not guaranteed though as even though "Federation" was officially dropped in 2002, it took a while for fans to catch on (despite the "get the F out" campaign) and Federation was still part of verbal vernacular for some years afterward.