Apostate prophet sits in the shade; How does the Sun reveal the shadow?

In answer to the video "43 Scientific Mistakes in the Quran"

In 25:45 it tells the reader to look at the shadows' movement, spreading and contracting. It then says the sun is the dalil/proof or indicator of the shadow's movement, not the other way around, with the shadow being an indicator of the sun's movement. This is because without sunlight directly hitting an object, the shadow wouldnt exist and there would be no proof or indication of it spreading or contracting regardless of the earth's movement around the sun. Try standing outside in daytime without sunlight directly hitting you, where is your shadow, do you see it contracting and spreading? You dont, despite the Earth's movement around the sun. Now try again with complete sun exposure. You will see your shadow spreading and contracting, because of its indicator, the sun.