Balk, or not?

[Rog]

NFHS Rules:
SITUATION 16: Team A's pitcher engages the pitching plate with both hands together in front of his body. R1, on third base, breaks for home. The pitcher steps off the pitching plate sideways with his pivot foot. The pitcher then throws to the third baseman, who throws to the catcher for the tag on the runner.
??? Balk, or not.....