-My biggest problem with all of the ethereal explanations...
How does an unidentified aircraft get into US airspace without a transponder signature and no immediate challenge by the Navy or Air Force?
How does a slow moving subsonic aircraft that is supposedly at least a two or four engine configuration only show one contrail?
How does an international airport the size of LAX fail to identify any commercial flight traveling through the area?
Your first and last questions are strawmen. Nobody reported missing any planes that day, period. Nobody has reported any radar or visuals of anything besides a few pictures and this video of a plane.
Compliance is word one. A single contrail would signify outbound from the source. Thirdly, that ain’t no dual or triple jet big bird coming from Hong Kong or anywhere else.
That is a launch.