i would after the sitting put in new engine oil, impeller , maybe plugs and fresh gasoline istead of oil in the tank . if you go too rich the guy on the ramp will not pay you the clogged carb rebuild, adding very little will do not have any effect. lubricating the cylinderwalls with this method on a 4 stroke with a pressure oil system cannot be serious.
generally speaking everbybody can try to run a spark ignited petrol engine on diesel fuel to check out how happy the engine generally is with oil based fluids in the combustion chamber.