To clarify a little, some MP games, you can't do anything with on the client, as the server will not have any of it
Let me take an example here. I've been working with CoD5 recently, just for fun, hacking on a LAN game (so as not to annoy anyone on the web).
I found ammo and weapon fire-rate to be server-sided. That is, no matter how much you try, you cannot override it from memory editing on the game client. On the host machine, I can set any of the current player's ammo or gun fire-rate to whatever, and it will take effect.
However, recoil and weapon accuracy are client-sided (that is not server-sided), meaning that you can edit these variables on the client and have it take effect. I am no expert in this regard, but I would suspect these calculations if done on the server would cause way too much overhead. And that is why it is left to the client.
It is therefore down to anti-cheat systems such as punkbuster to scan for any of these 'possible' memory alterations and kick/ban cheating players online. Many people did use Recoil hacks on CoD4 when that first came out. I can remember punkbuster taking an age to kick them (a bug which will have been fixed quickly though, but you get the idea). On a LAN game, without punkbuster (or another AC) enabled, it is a great way to test out what can and can't be done with a game.
So in your case, you can see why i'm not suprised that it doesn't work. I've never played this game, but i'd hazard a bet that there isn't even really a big game client to speak off, perhaps just something you access through a web browser, and login to a profile online. A profile which is stored on the server in it's entirety and one which you can't possible modify unless you comprised the server itself.
I don't make a habit of hacking online games of any kind, but that is general idea from what I have discerned over the years
~Psych