The lift vector is acting upward from the hub, being the point where the force from the rotor is transferred to the mast and hence the rest of the machine (plus a little bit from the tilted tail rotor thrust).
The reason the CofG isn't directly under the mast is because of the tail rotor thrust displacing it from there.
The main rotor disc tilt opposes that side force to stop the drift and, in the process creates the roll.
Nick, I must admit I feel a bit of a goat challenging a guy of your experience, but I honestly can't see why this diagram doesn't represent the forces on a teetering head helicopter in a stationary hover, albeit with some exaggerated angles for the sake of clear depiction.