1. Thailand may well fine CX for boarding OP without proper entry docs. CX may pursue OP for that fine which may be a quite hefty amount. Were I OP I would say nothing and just pray that Thailand doesn't act against CX.

2. It is 100% the passenger's responsibility to present the proper documents for admission.

3. Carriers rely on IATA's TIMATIC database to determine what docs a passenger requires. It is available free of charge at the link below. You input the variables and you will see what the agent will see onscreen.

http://www.staralliance.com/en/servi...sa-and-health/