I have seen snakes in the wild that had healed from horrific looking wounds.

There is an older Eastern (Sirtalis Sirtalis) that moves through my back yard we named her "Scar" She is fully wild, and I have only picked "Scar" up a few times to check on her.

Oddly, no sightings of "Scar" this season, but for the 3 years prior right around mid July, "Scar" would show up under a sheet of plywood behind the barn.

Snakes are really quite rugged when they are healthy.