I actually have a Scorpion and asked CZ-USA this exact question...
They said that the SilencerCo Omega 9 with a three-lug mount is the only configuration they recommend. And, if you want to change from a pistol forend to the carbine forend it's designed specifically to fit inside the handguard. Apparently the two companies collaborated on the suppressed Scorpion carbine from what they said.
I have a Rugged 45 that I use for my micro-k. I keep it in the long configuration, just because I'm usually too lazy to change it out. It's amazingly quiet with some 165 grain subsonic rounds.
FYI - I have tried multiple suppressor configurations with the EVO and because of the blow-back design of the weapon you do get a fairly loud pop at the bolt. Even with a suppressor on the gun running sub-sonic ammo you will want to wear ear protection as it is that loud.