Great result.
Two days ago I tested my new Yagi on CE 5.8 GHz, after 1530 m I didn't lose signal but video became choppy (no fun to fly) so I returned. I just received Yagi so I wanted to see does it work, and it does. Main benefit for me is not max distance but clear signal in mid distances.
But there is a strange thing, I was away of town, landscape very similar like in your video, and before take off in Fly App all 2.4 GHz bars were red and long. Auto chose 5.8 GHz so I leave it in Auto, didn't switch to manual, and I used 5.8 GHz Yagi (is it OK to use it in that way, leave it on Auto?). But I expected that 2.4 GHz will be available. Maybe I should click to Manual to see if it will change, but while it was on Auto all 2.4 GHz bars were red and long. So even out of town I didn't see green 2.4 GHz channel. I think that I never seen green 2.4 GHz on mine Mini.