There is no suppression of free press in mexico by the military of otherwise. The state is in no way collapsing, no one here seriously thinks that, you are being misinformed. I have no love for the military, I think the drug wars are a terrible thing and I have no particular reason to defend the current government but the situation is nothing like what's portrayed on this article.
If you have information that the article is fake, I am sure the publisher would be extremely interested. Mother Jones is not to everyone's taste but I'm sure they would never knowingly publish false information.
Based on your skepticism I did look around a bit and the journalist has indeed now been granted asylum in the USA. One would presume that as part of that process his story had been checked out by the US authorities and determined to be genuine.
And if the reporter is not lying, then it implies the situation is real and probably widespread. If they do it for one guy, they can do it for anyone, unless you have some theory as to why this guy was made the exception.
I'm no Mexico expert but the brutal suppression of free press by the military is not new or rare, and is characteristic of corrupt or collapsing states. I find the story very believable, unfortunately, and thought that its dramatic writing style was very effective in driving home the seriousness of what is going on in Mexico.