This is the handbook commentary,
"Panelboards, time clocks, pool light switches, and so on, where located not less than 5 ft horizontally from the inside walls of a pool without a solid fence, wall, or other permanent barrier, must be out of reach of persons who are in the pool, thereby preventing contact and possible shock hazards."
You could easily argue that the deck is a barrier which prevents someone in the spa from touching the switch
