If this is my flight itinerary from U.S. to Thailand, at what point will I be asked to show all my documents? Am I going to show the TR visa, COE, COVID test results, Fit-To-Fly, & Insurance in AUS, DFW or DOH? The Thai Embassy states you must present these documents at the "departure airport", but what is the departure airport in this case?
AUS (Austin) --> DFW (Dallas) --> DOH (Doha) --> BKK (Bangkok)
TLDR : Answer Summary
When traveling from the U.S. to Thailand, you will most likely be required to present your visa, COE, COVID test results, Fit-To-Fly certificate, and insurance documentation at Dallas/Fort Worth International Airport (DFW), where you check in for your international flight to Thailand. It's essential to keep these documents in your hand luggage since airlines often check for required documents during check-in, and you may also need to show them to immigration officials.