Not very well hidden with the pink hat... would have worked better with a green hat, and if shot from further away to allow for a larger crop of the image.
Near the top of the shot wearing something blueish purple.... just kidding. the red hat makes it a little too obvious imo but hey I guess he doesn't have to be hidden right?
This is a neat take on the challenge, and I like the use of the bright hat to emphasize that you know we see your "Waldo" here. Cute expression, and some nice plays of light across the green leaves. The appearance of the blue flowers toward the back adds a nice touch.
Great color contrast! The only minor nit -- the eye "whites" look really blue. was that intentional. I can't vote on this one, but if I could, I would give it a 7 or so.
Image could be slightly more sharp. I like this photo and I would have scored this better in a different challenge. I feel that Waldo should not be the center of attention, but a secondary surprise that only someone who really looks into the photo can appreciate.
Make sure you have your white balance adjusted nicely, especially before boosting the colours. Everything has a blue cast, and it really shows up on their eyes.