Balk rule

[DavyDuke17]

I am a young player and I have a question regarding the balk rule that I can't seem to find anywhere else. Here is the situation, a RHP is from the stretch position and there is a runner on first. Can he pick up his left leg as if he is doing his leg kick, then rotate on his heel and throw over to first if his knee never crosses his body? It is kind of like a LHP doing it (The move Pettite uses) except it is a RHP. My coach tells me this is fine as long as your knee doesn't cross but my thinking is as a baserunner I've always been told when you are stealing on a RHP go once you see him pick up his left leg. You could never see if the RHP crossed his knee back or not from first and this would make stealing on a RHP even harder than stealing on a lefty if this is true. Can someone please tell me the right awnser?