Many cruisers nowadays are equipped with dashboard video cameras to record the actions of the officer and the driver during stops. The article never says if the vehicle carried one, but it might help clarify things. Also, in addition to the two soldiers, there was a civilian driver involved. In all traffic stops, the person responsible for the vehicle and its occupants is the driver. I've yet to hear what the driver's actions were or what comments he had to say about the incident. That could be telling also. Does anyone know?
If Robin Sage has been going on for 4 decades and "everybody" knows about it, then I would think that there must be some SOP in place, in the event one party or the other is unsure about whether or not they were taking part in a Robin Sage role-play excercise, to drop a code word or gesture, or the civilian tips the deputy with identification and a password about what's about to take place.
I find it significant that the Sheriff is coming down firmly on the side of his deputy at this point. He has access to knowledge that we don't and appears willing to face the court (and perhaps the voters, if his is an elective office) over this one. Then again, until the facts are clear, it may may be his duty to give his officer the benefit of the doubt.
Based on what I know at the moment, it seems to me the Deputy did his duty in resisting disarmament by unknown assailants. It's a terrible loss that one SF soldier was killed and another was wounded over the incident.