How about "Your Fucked."

You could also try this, but from what I understand, it works only in the N64 version. If it doesn't work, I'll come to the conclusion that the developers accidentally left the button sequence out.

Down, Back, Back, Forward, Low Kick

I already tried this move and it doesn't work.
But I also can't perform Johnny Cage's friendship.

Classic Sub-Zero's friendship: (close) Hold Block, press High Kick, up, up, release Block, then High Kick. I already did this and it does work on PS1 version.

Sorry, I make a mistake. I mean.. (close) Hold Block, press High Kick, Run, Run, Up, release Block. I believe this is work only in PS1 version.

i tried that move and it worked

It didn't work for me but there are some finishers harder to perform for me like Raiden's babality and I never managed to perform Johnny Cage's friendship.

legend_armlet, please try it again. If it don't work for you, try press High Kick, Run, Run, Up (close) or Hold Block, press HK, release Block, Run, Run, Up (close). I hope it will work for you.

Do you want to know how to perform Johnny Cage's friendship?
Johnny Cage's friendship: Down, Down, Down, Down, Low Kick (anywhere)

legend_armlet, please try it again. If it don't work for you, try press High Kick, Run, Run, Up (close) or Hold Block, press HK, release Block, Run, Run, Up (close). I hope it will work for you.

Do you want to know how to perform Johnny Cage's friendship?
Johnny Cage's friendship: Down, Down, Down, Down, Low Kick (anywhere)

legend_armlet, please try it again. If it don't work for you, then try press High Kick, Run, Run, Up (close) or Hold Block, press Hk, release Block, Rn, Rn, Up (close).

Do you want to know how to peform Johnny cage's friendship?
Johnny Cage's friendship: Down, Down, Down, Down, Low Kick (anywhere)

It finally worked for both Johnny Cage and Classic Sub-Zero.
I'm glad I can perform all finishing moves from MKT.