A miner investigating a vein of gold must bring his team of five back to safety when a string of seemingly paranormal occurrences drives the men to insanity.

Absolutely intrigued!

The mystery for me is the dog that isn't barking. To wit, how come the protagonist is the only one not driven to insanity?

Your logline suggests the inciting incident is a string of paranormal occurrences that sends his team insane ... so if they're insane, what does "bringing them back to safety" look like? And if the "safety" is just escaping the ghosts (or whatever they're encountering) ... why don't they just leave the mine? What is making that difficult?

There's no clear antagonist, beside a vague force, but I guess with ghost movies that's not so crucial? I'm not certain on that one ...

What else do you know about the miner? Is there some way to make him the ironic protagonist, or else give us a little more indication of the internal journey he's likely to experience?