This is the schedule   Grayson Rams - Hunter Green, Vegas Gold & Navy 8/12 North Gwinnett (Mercedes Benz) 8/21 At Sandy Creek 9/04 At Hughes 9/11 At Brunswick (Glynn County Stadium) 9/18 Buford 10/09 At Archer 10/16 At Newton 10/23 South Gwinnett 11/06 Rockdale County

So Grayson’s schedule on the GHSA list only has nine games listed. And neither Florida team is on it. So I’m assuming the Tenth game is against one of them, but who knows

The West dont play Grayson. Only carol city and the rockets play buford 

Something isn't lining up. I've heard from a few people that MNW was to be playing Grayson the same weekend MC plays Buford. Even heard a coach mention on a podcast earlier in the week. But as you said MNW isn't listed on the schedule. Also when you look at Carol City's schedule it shows Grayson, but Grayson's schedule doesn't mention Carol City. And when you really think about it, it would be a little odd that both MNW and CC would be traveling to GA to play the same team just a few weeks apart. 

Prediction from the peanut gallery.  There is always next year.  Go Cats!