Can I apply for a retirement visa in Thailand without returning to the US?

I'm currently in Bangkok on an STV that expires in October (already renewed twice), so I must leave the country. Does anyone know of best way to extend my stay? I'm likely eligible for retirement visa. My question: Since I'm a US citizen, do I have to return to US to get process moving for a retirement visa or do I have potential options of a border run to a SE Asia country (and then entering on a tourist/retirement - or other - visa)? I will be fully vaccinated (with Pfizer) in October. Thanks!

UPDATE: On October 15, I DID receive a COVID-19 visa extension for 60 days - even though I was here on an STV visa. Did NOT have to leave the country! I was able to show that a US-bound flight that I had originally booked was cancelled and that allowed me to receive the COVID-19 visa extension.

As I was leaving, a different Immigration officer told me I could extend again if I came back before November 26. (That was an unexpected surprise.) She also told me that I should WEAR PANTS instead of shorts when I come to Immigration! 😊 (I've been there several times over the years and I didn't know - silly American!)