There is a very, very easy way to fix his addiction. Are you ready for it?
Change the password on his WoW account. Lock him out of it. Don't give him the new password, and force him to spend a week off of the game. This is time he should be spending with his children and his wife. Sitting in front of the computer all day long can't be good for his back problems, either.
To change his password, go to the official WoW website. I probably can't link it here because I'll be accused of spamming, but type 'WoW' into Google and it'll be your first hit. Click on "Account Management", enter his account name and password, then click "change password" once you're in. Bing, bang, easy.
If his addiction doesn't improve after a week, go directly to his CO. There are ways to get him out of this cycle without waiting for some lady to get around to calling you back.