When we run our generator for air conditioning whenever in the motorhome or whenever gone from the motorhome with the dog left inside, we close up everything except the one roof vent with a reversible 3-speed vent fan in it. We leave this fan set to AIR IN and on it's lowest speed setting. This creates and maintains a small amount of air pressure inside the RV.
This small amount of air pressure keeps any generator fumes from entering the RV anywhere. Since the stock generator exhaust position as installed by Winnebago is way down low, the vent way up on the top of the roof does not pick up any generator fumes while it's maintaining air pressure inside. The cooled air inside the RV always smells fresh and fume-free using this method and no Gen-Turi is required.
In fact, if one's RV air conditioner was to ever have an air circulation "leak" such that some outside air inadvertently got mixed in with the air it circulates in the RV's interior, having a Gen-Turi exhausting up near the top of the RV could in fact cause fumes to wind up inside the RV whenever the air conditioner was running.