The main snag there is that you'll need to do something with the other three cave entrances. Of course, if you have four mini-quests on Aruba, you could have one in each cave.
Meanwhile, I've been making progress with the Arawak Burial Ground. In particular, I've been having fun with LocLighter. All sources of lighting apart from torches are disabled - sun, sky, and in particular ambient. The torches are brighter and have longer range than normal. The effect is that most of the cave is lit to some extent though there are still patches of total darkness. And I added a "candle" locator near the entrance, which is a long tunnel that goes round a corner, though you'll never get to that corner because the exit reload is before it. So the "candle" locator is out of sight and it's been set a lot brighter, whiter and longer range than any normal candle, the effect being a source of light near the exit so you have a visible clue to find your way out.
This opens up a possibility for your story, should you wish it. It would now be easy to make a new locator file with all the torches removed, making the cave completely dark apart from the exit light. The player would need to complete one of your other quests, then an Arawak could tell the player that a shaman has been to the cave and lit the torches. For amusement, if the player goes into the dark cave before then, you could have an on-screen message "It is pitch black. You are likely to be eaten by a grue." And then see if anyone gets the reference.
