Found a bit wierd stuff. I believe it's a bug. If a helot (decoy) decoys under marker - he would get benifit of surprise attack as decoy - is a MARKER But if the player chose the real model to be real - he would not. The funniest thing is that HOLOECHO worded in a diffrent way, whare HOLOECHO is a state, shared between model and markers, and explicitly allows surprise attack. Decoy do not.
Helot Decoys can't deploy in Marker form, the Decoy rules makes extensive differentiation between Decoy state and Marker state so Decoys should not be considered Marker states, IMO. Holoecho is different because unlike Decoy, it has a line that says Surprise Attack may be used while in the state. ► DECOY-1 and DECOY-2 Markers are placed on the gaming table when a Trooper is replicated in Model form, so they must be considered as Models for LoF purposes and may be targeted.