I refrained from commenting on the plot itself because I think your biggest challenge will be the actual player relationship dynamic and writing for that, rather than writing the story.
Your opening introduction of the blacksmith and a band of villains tearing through a village is a cliche. The idea that the hero didn't want to be a hero - and even actively fights against the role - has also been done before (and is becoming a trope). Neither of these things are a "bad" thing, it means you can look at many examples of this being done before and investigate where you can improve and change, it's an opportunity, but it means you'll need to try extra hard to draw the player into your game at the opening to keep them invested enough to reach your major plot twist.
Writing a religion into a game is very difficult, it can seems like an easy way to introduce external parties that affect the story flow (a god, a conflict, some kind of governing body, etc), but it's hard to write out religions.
I briefly explored the idea of a religion in my personal project's story and found that I was using it as an excuse to introduce an "Out of left field" element to knock the story into the direction I wanted it to go, rather than come up with a logical way to do that.
I was also using the religion as an easy way to introduce subtle back-story and discussion, but it turned out to be not-very-subtle at all and got in the way of the actual game-play.
Scrapped the religion entirely. Professional writers I know have even gone as far to say introducing a cult/religion is "lazy writing", but I disagree, I think the justification needs to be right and that's the hard part.
Consider why you've chosen a cult, rather than a malevolent government - for example, and consider the role your gods actually play in the story. Instead of using religion and gods as motivation, maybe turn it into a surprise "reason why" at the end? Rather than "gods tell us its bad, lets go" consider changing it around to "these people are bad, lets beat them. Wait, I've been doing this at the will of some god that we didn't know about? And that will was carried out by the player? I've been played!". That could play into your player-relationship dynamic and maybe contribute to your heart-torn ending (Les feels betrayed, the player feels like they were being played and have no way to convince Les that they weren't involved?).
There isn't much in your story to go by and critique. You need to consider motivations, personalities, the setting, where the game-play takes place, the timing, the size of the game area. At the moment this is a scenario idea, rather than a plot or story.