Like j_garcia said, it's not an issue with a solid projectile, but it is exactly the concern I have heard about the pistol shotshells. One of the TV shows, maybe American Rifleman, did a segment on it. Fire will escape the gap in a revolver between cylinder and barrel. If you've ever carelessly placed your support hand, you can confirm. The concern w/ shotshells like the CCI is that hard blue plastic shards may also fly out of this gap, or jam in the gap preventing the cylinder from indexing.
The thing I don't understand is why a 45acp revolver is not recommended, but a 38/357 is OK. Seems odd.
And yes, hitting a slithering snake w/ anything but a shotgun is nigh impossible for me too. So the snake needs to be still. And you need to be within about 6 feet of it for one of these CCI shotshells to work. They contain relatively few pellets, and spinning due to a rifled barrel will quickly expand the pattern to a useless degree. So the scope of these things is pretty limited, thus the attraction of a .410 handgun. BUT, since they also have rifled barrels for double duty w/ a 45 metallic cartridge, their range is also much less than a smoothbore shotgun.
So I guess if the snake is close enough to bite you, you can shoot it w/ a CCI shotshell. A 410 Judge will give you a lot more shot and a few steps greater range. But if you want to maintain enough distance so if the snake comes toward you, you can throw the gun, turn, and run screaming like a girl, I guess you need to stick w/ a regular shotgun.