I believe also that this spoiler was added, especially on an RS. I'm just wondering if yes or no, I'll put a rear "Camaro" emblem forward of the spoiler.
Rear spoiler on my '69RS was a dealer (or someone) installed item after the car left the factory. During the body/paint work fall 2013-spring 2014, I had the shop doing the work add the deck lid "Camaro" emblem. IMO adds a very nice touch.
Richard