For what it's worth, I also see the front left arm sneak into view on a tight right turn. However, I've never seen the exact effect you demonstrate, that seems more extreme than I get. I'm assuming it's the body going into twist due to out of balance prop forces. I get around by dropping the camera by a few degrees from horizontal and going steady on the turn.
Looks like it's flying into the wind but that's a lot of movement. Is that the stock camera or are there filters and a lens hood on it? Mine stays still when making turns usually and never that bad. Looks like a gimbal problem. You should start it up and then check for movement after start up at home. You may find something loose.