For an award the rules are different than for a revenue ticket. They are not published publicly but they are included in the nitty-gritty details that the agent has on screen when try to book the award. I've had pretty good success getting the agents to explain or read the particular bits to me when they declare a routing illegal but with my most recent effort on that front it did take a few agents until we actually got the correct text figured out.

ETA: Talking with the agent just now it priced at 40K with the NRT connection rather than 30K. She tried a couple things and essentially it is pricing the trip as a SB13N award. S=Standard, B=Business and 13N=award series. The routing without the NRT connection prices as an SB13 award. I would imagine that it would do the same with a KIX connection.

So it is legal but costs a bit more. Still not a horrible deal if you've got the points to spare.