Yeah...ummm....what "palm heel" ? I am familiar with a couple of variations on Lone Kimono, but none of them...(Including the one in the video you linked) contains a palm heel strike?
I mean, I know the "Ol' man" was fast....but apparently he was so quick I never even saw the palm strike?
Unless, you are referring to the left hand pin, as a "palm strike" ?
Otherwise my thought is..."Huh"?