The Mk.20 has the digital woodland camo pattern. Weapons moved from OPFOR's armory to GREENFOR's (from the transition of Alpha to Beta) still retain the desert/khaki-brown hex patterns.
Basically; the Alamut, the Vermin and the Mk.200 still retain their old color schemes and do not match GREENFOR's patterns.
EDIT: Since the ticket's inception, the Vermin has been switched over to OPFOR's inventory. PCML's are now used for GREENFOR's AT Infantry, but the Alamut is still present in their respective "launchers" crate. I have noticed the introduction of a "plain/khaki" Mk.20 to GREENFOR's inventory. That being said there are khaki variants of the Mk.18 and Mk.200, but no digi-woodland variations. I am unsure if these are to be implemented or not, and as such my ticket still stands.