^^^I never quite got past the scene where Tom broke into Harry's bedroom. And not just because we find Harry wears a sleep mask. I would have thought Paris/Kim was another canonical slash coupling like J/7, except it was two guys and interracial to boot. But, no, the alternate Tom was there to show us the inner, true Tom, who is incredibly noble and self-sacrificing. I have no idea how a society without money is supposed to be infested with ne'er-do-wells like alternate Tom or Julian Bashir's father, but there you are.
Paris' decision to save Harry is offscreen because seeing him come to the rescue is supposed to be a bravo moment. Harry's presumably dramatic decision to return to the ship may be technically on screen but it's not dramatized. There's no high point or exciting scene like Tom the Hero swooping in to save his friend.
Keeping the protagonist off screen isn't clumsy writing. But character based drama where the characters are acting out instead of interacting with the environment. There really isn't any reason why alternate Tom can't straighten up his act if he's really inspired to hope. Nor is there any reason why his situation is so dire as to merit suicide. (There's no reason to think any universes are destroyed in this scenario.) This weak motivation for Tom may be why the character didn't just dominate the story, even though all the heroics are due to him. Harry succeeds in nothing,
other than, presumably, pleasing Libby during the fadeout.