I think we should get it clear in plain words regarding the "co-pilot" position in an AS 350.
There is no such thing! As the aircraft is single pilot certified the person on the left seat would be a passenger. Or maybe a "supportive" crew member like a navigator or else. This person could not "log" any of his flight hours unless the flight would be classed a training flight and this person would sit on the right with a FI/TRI on the left.
Then again I doubt that you legally could class oprational flights (e.g.fire fighting) as training flights towards a type rating.
Only my two cent - I am happy to be corrected.