They've put TruOil on the fretboard first. It's not at all clear from the video, but before the wax, he does talk about buffing up to the frets, so he's definitely put TO on the board first.
I'm not a fan of putting wax on top of finishes, though a couple of applications of Carnauba wax is supposed to stop a gloss neck that feels sticky to the hand (a nitro finish trait when it's new) from being being sticky.