From my experience, the color of *most* animal's eyes will vary with the reflection of bright light...by that I mean, it depends on the angle you look at them, as well as the angle the light is shining on 'em.
I've not seen cougars eyes at night, but I have seen ferals cats and bobcats both show reddish orange, yellow, or green at night.
Years ago I was told that green will gather light the best...which is why green fiber optic sight pins on your bow glow better than the others, why night vision is green, and why a cat's eyes are green.
Wow, I'm rambling.