I was approved from the DC embassy recently. Mine took just under 3 weeks. Yours is at 13 business days today. If there were any Thai holidays, it’s less than 13 days. You are probably getting close. Hang in there.
I fly from Atlanta to BKK several times each year. I fly Qatar, Cathay Pacific, Turkish Airlines and, when on sale, Delta. Occasionally I find great deals using “multiple airlines” option in Skyscanner or Expedia
I am not sure how it relates going from USA to Thailand and back, but I got round trip tickets from Qatar airways for about $1200 usd. The key factor was it is with 60 days advance purchase. I did this last week.