Which method are you trying to use banked (฿800K) or income 12 deposits (฿65K)? If it is income you need a special statement from your Thai bank showing only the foreign 12 deposits. The 12 deposits must already be shown prior to applying.
If you apply in the US you would be applying for an O-A visa and have an insurance requirement. If you apply in Thailand it would be an O with no insurance requirement. But you would have a requirement a deposit in a Thai bank.
You may use your VA to an extent but it would probably not be on the list of acceptable insurances.
So your choices are get a different insurance or keep ฿800.000 ( for the most part) in a Thai bank.
more like 5 or 6 years ago. Not really nesting, just IO trying to see if you had the requirements for the previous year. If someone got a 2nd extension based on banked money they would be asked for proof of money in the bank for the previous year. So immigration COULD ask for the proof of banked money in the bank for the year before switching to income.
in my case I never had the 800k but I did have a "simulated" 800 from an agent. After my 12 plus 3 months I did 12 consecutive deposits of 65K +. So when the new extension was due I just used my my 12 FTT deposits. IO did not check my previous "800K" but they could have if they wanted.