| Alright, well the word is in, the Spec Ops achievement cannot be glitched over from one account to the other, what I thought was glitching over the achievement, was just the achievement unlocking after some random game on fresh account.
What this means, is that if you have a new account, never downloaded the red/black packs, you don't even need to do all 57 games, it will randomly unlock for you at anytime, 6 accounts and I've had it unlock after 1 game, 1 game, 7 games, 24 games, 32 games, and 50 games, and many of those games were same map and adversarial mode.
However, I may have a fix for the few people the original fix did not work for.
I went and confirmed with the people on my friends list, and their friends list, that got the achievement the way I described, and they all downloaded the new maps, but never actually played them. The one person who it didn't unlock for, played the new maps, many times, this may be whats causing the problem.
So we did the exact same procedure, except we did ALL the games types on ALL maps(old and red and black maps). It was very time consuming, and the achievement did NOT unlock. We decided to have him delete the red/black packs anyway. We played another game, still no achievement. Next day, played a random game, achievement unlocked.
So while I cannot guarantee this will work, it seemed to work for him, and it may be worth a try. | 
Fix for the Special Operations achievement
Linear Mode
