Sorry DRZ119, but that's one of the wackiest comments I've read in quite some time.
The Los Ancianos MC created the Tecate Enduro many decades ago, they're the ones who's built ~99% of all the trails in the Sierra Juarez, they're the ones who've created and maintained good relations with the locals in the area, they'd need to be the ones to make it happen, they're the only who could make it happen..
The other 3 mentioned have never made a trail in the area, or dealt with the local ranchers or local politicians. Why would they be "great candidates"? Because they are active on social media? Makes zero sense IMO.
Actually, if the Los Ancianos wanted to see it happen and needed more help I'd say that the Tractor club or CODE would be the right go-to.
Fact is though to do a multi-day long enduro would be so extremely difficult these days. Too many land owners, fences, land use studies, permits, hoops, etc..
And IF the Los Ancianos said they would make a 2-day enduro like the old days they probably wouldn't get many entries because their events were so gnarly that very few finished and these days too many riders want to talk and type about gnarly events rather than actually compete (see King Of Motos). Los Ancianos had to start making things easier to keep entries even with 1 day events.
It's unfortunate but there really isn't the "large market" you think there is.
You want as close to possible of a Tecate 500? Join the fun on December 3 for the Los Ancianos most recent incarnation of their iconic event.