What happened to Andy Guo flying across the Yellow River?

I watched this video many times and finally found the flaw. First of all, it cannot be said that the entire audience is dragging, but more than 80% are dragging, and it is possible that only those six people are dragging. Have you noticed that there is no one behind the high platform across the Yellow River, and everyone's perspective is limited to the front of the high platform. First of all, I won't go into details about the preparations. When the black cloth covered them, they hid in various ways (a measure commonly used in magic), and then the black cloth flew to the high platform (I don't know the details, everyone knows it, and must have used it. Some kind of tool.) When the black cloth arrived at the high platform, the white smoke first blocked everyone's view. The key is here. The video was processed. The three people on the high platform did not appear directly, but were hidden behind the high platform in advance. . The last shot of the three people appearing uses the video fast-forward method. The three people came out from behind, with the white smoke blocking their view. You will find out if you look closely.