I don't know if anonymous claims should be given much weight in the first place, but I will admit to not following this story closely. Also should a journalist reporting these issues also be reviewing games from the same company? It just seems a little too entangled to me. He's obviously in contact with someone who has a beef with the company, either a legitimate beef or a axe to grind, so now I expect him to be able to review a game from the company without slant. That seems a bit messy.
Also, not having review codes doesn't prevent you from reviewing the game. Some professional reviewers just buy the games themselves, right? You don't have to play nice with any company if you follow that path.
And then the other issue, why is any company obligated in the first place to help anyone report on them? Well, I suppose the answer comes down to Metacritic aggregate scores and promotion in a general sense, but I don't really believe journalists are entitled to free stuff, access, or review copies or whatever. That's just my view on the matter.