yes my friend used this policy for his Thailand Pass (TP) only three months ago google Sainsbury’s travel insurance and there’s a phone number you can phone and ask any questions you have regarding quarantine, covid Asymptomatic good luck
Give SCB bank a try and if unsuccessful try another SCB bank or Bangkok Bank just don’t take no for an answer it would be good if you had a Thai girlfriend with or if you are desperate try a Agency they can help you for a fee good luck