I’d be fairly confident that it’s not a ’99 as the chainstay yoke is definitely forged and not extrduded, plus that’s a dead ringer for a Yeti-frame in other areas. I’d guess it’s a ’97ish Yeti-made Factory that got re-sprayed with some creative decal usage. The only place I’ve seen the green Homegrown Factory logos is in the beginning of the ’97 Catalog on the full suspension frames shown in the action shots (but not actually on the model pages).
Regardless, it’s a sweet ride.