Hey, I'm wondering if the enchantment script on an explosion will persist even after the explosion has stopped, and if it doesn't, how to stop it via script, thanks!

The script should end when the explosion is done. Since the explosion is automatically removed from the game when its done, its script would be removed as well.
Otherwise your game would suffer from extremely terrible game save bloat.

Actually scripts on Explosions are run once just like anything else they hit their AoE range effect what ever is in the radius and the script can run any duration after that if its set to run for a year in game it will, if you need something to have explosion area permanence you have to use a Placed Impact Object to create a second object that needs to be scripted to do what you want then you have to make sure you poof it with Disable -> MarkForDelete.