You know your company makes way more money off of this guy than he's paid and that he's the most productive so it absolutely does not matter if he pulled back a little or not. In fact, for all you know the other people on the team are always pulling back but you just assume that they aren't. In that case they are way more of a liability than he is.
If I'm in your shoes I would be going to higher-ups and telling them that the guy needs more money. Why don't you go to bat for him instead of viewing him as the enemy? Imagine what he could do when he actually has what he's asked for. Maybe you could even cut a less productive team member, eh?