Just to confirm a couple of points, and sometips:
This achievement is easier if you do not have any losses, as this counts against you. It must be in ranked online play, but can obviously be boosted with either a helpful friend or dummy account. At the time of writing, you should be able to achieve Champion status on the Submission leaderboard at about 60 wins. You also need to view your position on the leaderboards, making sure to select the correct leaderboard as different match types have separate leaderboards and champions.
The quickest way is to select the 'Mexico' arena and 'Submission' match type, and select AJ Styles. Walk to your opponent and hit LB + A to hit an Insiguri kick and lay your opponent down. Walk around and stand behind the head of your opponent and repeatedly hit Y to fire elbows on top of his skull. Seven or eight hits later, the head part of your opponents health picture should be dark red, so hit LB + B to lock in that submission and hit three x three button sequences to finish the match. This can be as quick as 15 seconds, but with matchmaking and loading takes approx 2 minutes per game.
Edited to add: Having finally finished boosting this (Thanks DivineWind72!) the ranking (with wins I needed to achieve) goes:
Journeyman (55 wins)
Up & Comer (56 wins)
Superstar (57 wins)
Main Eventer (58 wins)
TNA Champion (59 wins)