caver;
Reviewed the video and between the bridges, houses around an old farm area, and a few other details, anyone familiar with the area would know exactly where to go and begin searching. The horseshoe, knife, and the long piece of metal may have been directional indicators.
If you are unfamiliar with the use of a compass and topo map, you really need to learn how. There are a number of people here on TN forum, including myself, that would be willing to help you in this endeavor. I said the "metal may have been directional indicators",
if they were, the line they indicated is most likely lost...forever.
Should you dig another piece, don't move it, see if it has a shape, usually pointed, showing the direction you should go to the next mark. Use a compass to get the line, and record the info on your topo map. Take a lot of photos, but try to limit the amount of background as much as possible.
There's a lot of info on this forum about how to do and go about doing it the right way. Please take advantage of it, you won't regret it.