Andrew Chan thank you for clarifying this, He would have never made it with a "normal" visa. I have never heard or read about this option. It would have been up to IVAN to explain it further as not to raise confusion around Non-APEC members
hhhahahha that's a good joke, opening the week ! You manage to go through the "self-check-in" and their computer/robots/machines are too dumb to notice that you actually should not have been permitted to board this flight. I would say: TIT (This is Technic)
the German Embassy has published on their website that they will NOT under NO circumstances issue the letter to you. They advice you to go on standby at the airport and get back to Germany ASAP
you may have to self-quarantaine yourself when arriving to the USA. You should check the websites of the US government or the IATA list of countries and their air traffic updated regulations