It is certainly possible but you are the first guy to say the hatch was not there. This is puzzling as the laser cutting file is like a CAD file that is sent to the laser cutter and should never change. Only thing I can think of is something could have interrupted the process and stopped the cut??????? Still a very unusual situation. Should be a simple rectangle from the 1/16" ply with a hole cut in the middle to lighten it up.