I am not suggesting returning him to the wild to be mean or anything. It's just that the wild populations are in serious trouble. Plus they don't always do well being made into captives. My suggestion, if your really wanting a turtle or tortoise after being around this guy, is to rescue one already in captivity and needing a forever home.
I think he must have been a pet. It was in a highly populated area, no wildlife around at all. Do you really think he could be wild? I wouldn't have brought him home if I thought he was, but there was a cat after him. He at least needed to be relocated...what do you think?
It's a male 3toed box turtle. Whether not it was a released pet or a relocated wild specimen is darn near impossible to determine. If you do end up keeping it I would suggest an outdoor enclosure above an indoor. But I can tell you from experience male 3toed box turtles in general are escape artist . They need a moist environment preferably with an available water dish and a good play to dig down and hide(cypress mulch). Food should be a good mix of fruit/veggies/worms/grubs/wet dog food/ bread/etc. good luck with whatever you decide.
I just noticed he has four rear toes, he must be in a gulf coast/ 3toed integration area. Very interesting !! What part of Louisiana are you from?