I had to provide them with this information. All sent via mail from UK to Bangkok
Copy of Insurance Policy.
Copy of Passport.
Proof of travel stating the date of entry into Thailand, such as the passport page with the date of entry stamped or Travel itinerary from Airline.
Doctor/ Physician's report describing significant symptoms, diagnosis and result of treatment.
All Treatment history from the admission date in hospital to the discharge date from the hospital.
All Original receipt with description of medical expenses or summary statement of medical expenses and receipt.
I'll follow up on the paths suggested above. Thanks for your help and advice.