That would be awesome. But unfortunatly I think those are just Ideas they had for this game that didn't make it. But who knows.

What was the name of Quan Chi's realm?

I like your theory because it might be possible. A possible way to such a realm might be through the netherrealm where you had to awaken kochal(however you spell the name). The new portal only took you to the entrance portal for the netherrealm with a 1,000 onyx coin reward. I just find it hard to believe that is the only reward for the tasks needed to open it up.
I think people just need to sit, relax, and be patient with the super unlockables. Boon wanted it to take sometime before the codes would come out to the public. The game is only a little over two weeks old. I personally did not buy the game for secrets; I enjoy it already for what it is. If there are codes....give it time and enjoy the game.
If anything, there will be extra puzzle kombat characters, fighting characters, extra death traps on already existing arenas(beetle lair or artifacts level) and a hidden arena; my predictions(I could be very wrong....who cares because I love the game for what it is). We already got our multiple fatalities that we all wanted because deadly alliance didn't have them.

I am going through Konquest with a new name and am not unlocking the chest by moloch so Cyrax and Nitara are still there now they have not dissapeared. Maybe we need to not open the chest until a later date after beating the 3 opponents. Also, We may need to wait to open the chest in Neatherealm where Johnny Cage and the other guy are fighting until a later date.

Cyrax and Nitara still disapear once the bridge is able to be passed. If you're going to skip chests, skip all of them, apparently greed is not liked in this game, as the white question mark insists.

And why did I get shot down when I brought up this same idea? :P
I think it's possible. My take was it could be a secret mini realm that offshoots from the Netherrealm and is possibly connected with the Kochal portal. But I guess it's equally possible that it's concept art for stuff that didn't make it into the game.

The idea of a new realm would be great, its the only way where we could unlock greater things. Perhaps Quan Chi's Palace or Pyramid might be awaken in THE NETHEREALM. It will rise up from the Lava lake

It is called Quan Chi's Realm on the production art. It even shows a picture of the portal when you enter the realm. I did think that it was just a "working prototype" but why would they have 3 different pictures at 3 different angles if it was not in the game? That's why it stuck out to me and they also developed a whole story behind it. I sure hope after we get all the jewels in the star the portal in Netherrealm opens up and we can tranport here.

now i could be wrong but from what i understood....that was going to konquest...having to fight through the differant towers to get to qun chi...but they changed it and scrapped the hole idea i think! QUAN IS DEAD!

I agree that Quan Chi was dead. But then I realized so was Liu Kang and so was Raiden but they are back also. I guess all I am saying is that they knew that Quan Chi was going to be dead before they made those renders, but they still made the renders. So I think they are going to work him into the story some how.