They are both in orderrealm and you can't play as them.

No one here knows to my knowledge. Some say there are no SU's and other say there are. But, I don't think anyone knows.

People know they are just in denial over the facts
http://www.mortalkombatonline.com/content/forum/showmessage.cds?id=37467
here you will see a mod of this site stating clearly that there are none according to the midway staff.

im not sure abot them but check this out....i found this in a thread....i thought it was bs till i seen the pics...this was the thread..his name was Geemaster13...here is the link...http://www.picturetrail.com/elranzer......check out pic 7&8...well look at em all mainly 7&8 and the last 2....but they are all cool...and it makes you wonder and hope..........................yes i do think their are SU's ...now more than ever....if anyone finds them please help us out...ty...he of little faith.....deception73..

They are just done with cheat devcies.

Funny.. I could have sworn Rare repeatedly denied the existance of the rare eggs in Banjo Kazooie, and no one could find them after having the game hacked apart. Then a few years later when everyone ahs all but forgotten about them, someone uncovers them.
It goes to show you two things:
1. Game developers aren't always truthful
2. Even though it might not seem like it, there is always a chance that something new will be found. Leave the hunters to their work.

You COULD have played as Stryker but this is what happened when he tried to get into MK:D(Look at my sig to see what happened to Stryker)

They are all rumors... just like Noob in MKDA... and ermac in MK 1...

Regarding banjo. I went and looked into it. First off the secrets were avialable with cheat devices unlock MK. Second they were different types of secrets. MK has never had a super unlockable before. The rest of the game is OBVIOUSLY unfinished so why would they include super unlockables when they couldn't finish other aspects of the game? When has it taken more than a month to find anything in mk. See with banjo the devices showed there was a possibility with mk they show there are not any. There isn't even an indication there are any super unlockables on this game unlike banjo and don't give me the crap that mk always has super unlockables in fact I'll deal with that now. Mk 1 no unlockables period one minor secret. Mk 2 no unlockables either 4 minor secrets 3 found day 1 of games release. MK3 no secrets one unlockable. UMK 3 unlockables no secrets. I didn't bother with 4 it was horrid. DA two secret unlockables nothing difficult about getting them though.
So what you are telling me is that a company that didn't even have time to remove universal tracking and make it so people can't combo off throws that don't juggle managed to do what nobody has done before and hide characters in the game with full move lists and tossed in decoy characters with no move lists to counfound the hackers. Yah ok and santa claus is real too.

There were 2 unlockable characters considered SU's these were Liu Kang & Raiden. No one on the development team though people would fins them, at least Kang, so fast.