The cargo seats with FFV functionality in ArmA3 base game as well as with the other vehicles in the SOG PF DLC have their cargo seats flagged with dontCreateAI 1.
The Cayuse instead have this value set to 0, which feels inconsistent (noticable for example if you createVehicleCrew and with every other vehicle you will not fill up passenger seats but you will on the Cayuse)
Vehicle config on Cayuse. No need to reproduce anything, just look at the difference in how cargo seats are handled on the Cayuse vs the other helicopters in the DLC.
Here is Apollo's explanation from the discord:
Apollo — Today at 5:53 PM
On the OH6-A, there is a pilot and 3 turrets (copilot, right door gunner and left FFV).
Apollo — Today at 6:11 PM
The reason that the OH6-A adds the FFV crew member with the createVehicleCrew command is because we have set dontCreateAI = 0; in this seat's turret config
Apollo — Today at 6:24 PM
FFV seats are only ignored because dontCreateAI is generally set to 1, but it's not necessarily so.
Yes, it is slightly inconsistent for this FFV seat to be spawning with crew, we'll review the design decision to check why it was done like this.