Watched the video.
So what you are telling me is that the 7D2 with the right lens (at 100mm) is better than the 5D3 (with the wrong lens) at a similar focal length.
I didn't watch the video. But if the OP is comparing the 7DII + 70-200mm f/2.8L IS II (arguably the best zoom lens available, at least the best under $10K), vs. the 5DIII + 24-105mm f/4L IS (a good lens, yes, but not nearly the quality of the 70-200 II), then I suppose I'll have to fetch my broom and declare shenanigans.
With the 7D2 and a 70-200mm lens, I can get 360mm framing with 5D3 ISO performance in a lightweight package.
If you're suggesting that image noise of a 7DII image and a 5DIII image with same lens/distance cropped to APS-C FoV are similar, ok. If you're suggesting that the high ISO performance of the two cameras is similar when comparing the same framing (e.g., a longer focal length on the 5DIII, aka 'using the right lens'), then try the comparison again once the effects of the mind-altering drugs have worn off.