Unfortunately it's still pretty hard to tell much from that picture- the frog is out of focus. Most cameras will let you half press the shutter and the camera will then lock the focus onto something. A full press will take the picture. Things that can go wrong- the frog is closer than the minimum focus distance (this seems likely here, the specs should be in your camera manual) or the camera has decided to lock focus on something else. I suggest the following:

-If your camera has a 'macro mode' you should use it (it then knows to look for close stuff).
-Zoom in to the longest focal length (most magnification).
-Aim the camera so the frog is in the centre of the picture, then half press the shutter button and wait for it to lock the focus onto something.
-If the frog is still blurry, move back and try again.
-If you're worried about stressing the frog by taking a bunch of pictures, you can practice on something frog sized until you figure out how to get a clear, in-focus picture and learn the limits of your camera (reading the manual can be a help here).

-Alternatively, you seemed to have better luck with the camera you used in the photo of the two of them together in post #5 if that ones still available (it has a different naming scheme, so I'm assuming that it was a different camera).

Your main concern is still the colour right? Are you very familiar with the natural variations of bullfrogs? If not, you might want to spend some time looking at pictures of them. Their natural array of colours is quite staggering (these are mostly the right bullfrogs): https://www.google.com/search?q=amer...w=1680&bih=889

A vet isn't wrong if you're still worried and have a qualified one nearby.