JV,
Spoilers generate a roll rate and a trimmable horizontal tailplane can generate a pitch rate (accepting that its use is to achieve zero pitch rate). Therefore, by the definitions that you have given they most certainly are primary control surfaces, a view with which I agree.
Personally, I believe that any disturbance of flaps also should generate a MCF because if one is misrigged then a significant rolling moment is generated which may mean that the nominal roll trim setting for take-off results in an aircraft that is out of roll trim at take-off.
Rgds
L