Something doesn't add up here. This guy claims the game must have a counter for all ammo pickups (which is false, these findings are from a maintenance period when the devs went through player inventories to find rare items that are obviously duped) yet he has 225,000+ of the most rare ammo in the game and only 72,000 of the most common and usually found in increments of 500, so that still wouldn't account for the ridiculous imbalance.. The guy was duping without a doubt. His convoluted description of giving items between his characters is simply a means of trying to say if I duped, it was an accident and I don't buy it. Dude got banned for cheating just like the pc players who modded to get into the dev room. The guy who glitched into the vault didn't get banned because it was a legitimate glitch. Dude's just butthurt he dedicated so much time just to get caught cheating. You can argue the duping is a glitch too, but it's a glitch you have to know what you are doing to make work, it's not something you just happen to stumble upon 500 times.
EDIT: Also, his total hours don't matter as much when you see that the offense took place within a 30-day period. If you go by the average someone calculated earlier he apparently got all of these items within 279 hours, not the total 900+ they have been playing.