You can tell by looking at the bite if the snake was venomous or non venomous.
Fang Marks. Non venomous snakes don't have fangs.
All of the venomous species of snakes in North America are vipers, with the exception of coral snakes.
Vipers leave two distinct fang marks.
Coral snakes are rear fanged, and need to bite and chew to inject venom. But coral snakes are distinct looking and would never be up in a tree. You would need to handle a coral snake to get it to bite you.
This is beyond silly. Are we supposed to believe people from Alabama are unfamiliar with snakes?
(I myself saw a Rat Snake of some type in AK, and a dead Milk Snake in Magic Kingdom.)
Good thing these people didn't see an alligator near Splash Mountain, or heaven help us - an Anole!