Asteroid - NEO candidate
Nice example of asteroid at the 4 o'clock position. It wasn't mark as a known one.
That is a nice find and this is definitely something on an unusual orbit! Main belt objects all move in very similar direction with very similar speeds (in these images taken close to the opposition point). This one is moving almost the exact opposite direction and you can even see trailing due to much larger apparent speed.
This was definitely picked up and reported to the NEOCP (Near Earth Object Confirmation Page), and although unknown at the time the data was taken, it surely was recovered and received a designation afterwards.
p.s. could you please edit the title adding something like "FMO" or "NEO candicate" - thanks