But it's hard to care or feel anything for a protagonist that is so dumb. Kill the beast. Then loot his cave.
Okay, seriously, if you're going to comment, read the post. That's a story criticism. And it has absolutely nothing to do with the video. If you can't feel any emotion for the MC, then he's not a good character. The reader needs a reason to care, either by rooting for him or against him.
And in fiction, there is a thing called "suspension of disbelief." The moment you break your readers' willingness to suspend disbelief, you've failed. The big reveal of this story is that the planet is, in fact, Earth. Therefore, if you want the story to make sense, you need to abide by the scientific laws that govern Earth, or otherwise explain them away with something credible in your plot. This story does not do that, and that undermines the entire premise. Just slapping something into a story because it's "cool" with no bearing on the plot or logical rationale is weak and lazy writing. And this is the same reason why Deus ex Machina solutions are garbage and mocked.
Now, I understand this is your brother, and you want to stand up for his writing. But no one gets any better by hand waving gaping holes in the structure and plot.