With the new pictures I can understand your thoughts that this is an error and not damage. But I am afraid I still have to stick with damage. It looks like the coin was smashed between two different materials. The obverse was smashed against something hard (like metal) with a hole in it. The reverse was smashed against something softer (like hard wood, plastic, hard rubber, ect) that conformed around the detail then applied pressure to the reverse protecting it. It is hard to tell from your photos but I think there is some metal pushed out at the edge where UNITED is on the reverse and the higher fine details on the reverse appear fuzzy (such as the sharp edges of the letters and the leaves) but this could just be from the fuzziness of the photo. So even though it is a clue to authenticity a coin can become damaged on one side while not being damaged on the other. It just means you need to look closer. Check out the detail and the edge to see if it is just from the photo.