I am interested in seeing the chart you made. I have my own method and am able to nearly 100% the intro using it. Here's how..
I tilt the guitar straight up and down so the end of it is near my face. Using my chin, that's right, my chin, I hold the green button down through the entire section. I use my fretting hand to quickly (and I mean
quickly) tap buttons red through orange, and use my strumming hand to strum down on each of the notes except the greens.
Theoretically, I could probably just strum once and play the whole thing, but I find the strumming helps me keep the rhythm with my fret hand better.
Sure I look funny, but not as funny as the guy I'm competing against (I compete in local tournaments for fun)!