I’m guessing it’s a 4chan troll blaming it on 9gag with a random id. I searched JamesHolmes154 and nothing.
Interesting. Either scrubbed almost immediately or as you said- some kind of troll.
Normally by now in this kind of incident we have the perp’s facebook page and all sorts of background info on him- so far all we know is his mom isn’t shocked and he got a traffic ticket in 2001. Odd.