When you say it doesn't work at all, what do you mean? There's no reason it won't read at least the "ok google" at the top of the screen, but navigating around probably won't work here.

I don't have a mac on hand right now, but VoiceOver relies heavily on tags, so i'd bet the problem is that he is using divs for everything.

Make each thing on the left render in an <li> and use header elements at the top of each block of commands and it should work fine.