If it makes you feel better the first time I did this move (I was having RP goes as everything else was wired) I got a little further (stoop up and clipping off another Egyptian?) and shouted 'slack' which was misheard by my wife who ran backwards (thinking take) dragging me off. I had a moment of futile resistance.
I think (but it was now a fair while ago; ~2011) that my right foot was higher than the obvious place where people do the Egyptian and may have padded the left upwards.
Thankfully the next time I did the move it went. I recall Johnny Brown (moaning about "out of gamut green") being there snapping photos (of which I have a few) perhaps he might have some others which I don't posses which show the sequence clearly? I can send you the one I have from lower down via Twitter but I'm not sure it'll help much.
I dont recall the exact details, but I did it with beta similar to yours, going left hand to the crimp rather than going again with right. I think it involved a bicycle with feet to work and was a very fast slap.
It did; I remember trying this sequence at the time and it was unfathomable.
JB also kept referring to it as the route "Caff couldn't do" which did make me feel better.