I'm not sure where you're going with this... double damages means double damages. They doubled what they believed was owed to him. i.e. the second $38,385 was not simply "unpaid labor" it was damages in addition to unpaid labor. And the remaining $18,249.13 in attorneys fees and "interest" which also isn't unpaid labor.
Again, to my original point; even if Bungie believed they fired with cause, never agreed to pay anything to Marty as he states in the suit, and had provisions to withhold certain benefits/etc.. he's suing for considering he was terminated and didn't resign, it's still much cheaper to settle this way than to spend thousands more to defend themselves even if they eventually won.