It's utter nonsense, sorry. We don't release death figures until you have a confirmed body, and that's really hard to do in a structurally unsound building which suffered such severe fire damage. It's not some ridiculous conspiracy, the number will be updated as time passes.
Also, if you think that there's a "true" number being used by the services and it hasn't been leaked to the press, or the press have agreed to conceal that number, you're mad. That just doesn't happen when it comes to stuff like this. It would have leaked *somewhere*. The press will assist police by not releasing details of an attacker after an incident, they won't conceal a body count.