I still have the frog! He or she

is actually outside in a container and has not tried to escape. I tried to let him go one night only to go outside the next day and he was still there. So I put in him a shallow container (uncovered), with 1/4 inch of bottled water and some leaves from our trees. This has been over a week now and he still hasn't tried to escape. I am hoping at night he is getting some insects, but not sure. When I pick him up, he seems fine, he walks all over my arm. Anyhow, we are in TX, north of Houston in a wooded area. I am thinking he is a green tree frog, and he actually changed color from bright green to spotted olive color and now is getting green again. I read this might be from humidity and temp.
I would ideally like to let him go, but worry he won't survive (and wonder where the best place to let him go would be). On the other hand, will he survive any better in captivity until he heals? Am I able to post pics on this board? If so, I will take some and post! Thanks for your response!