1 - The game was created by Fen, so it would be up to Fen as to whether or not it would be added.
2 - Steam requires a payment of approximately $100 to add a game to the service. Thats not much of problem but in order for Steam to start paying developers, the game must earn $100, which thanks to some legal loopholes in their contract, a game must actually earn $400 before Steam will start paying out. Now ask if that's worth it for a game that has been completed and free for several years.