I just wanted to confirm that this did fix my issue, the cylinder head cover (aka valve cover) is essentially a PCV valve....In the below pictures you may even be able to see the failed diaphragm seal in the cover....
My initial post Loud whistling noise from engine
The top of the new cover, and the underside of the old cover.
Closer up of the PCV valve.
The top of the engine with the cover off, there is nothing there but two open holes to the crankcase on the drivers side.
Visual confirmation of the failed valve.
The new cover installed.
Thanks again KatieMichelle!!