The advice is don't apply for a non-OA visa. Why are you applying for that? It's only useful in very specific circumstances and is not the proper visa for most people. The non-O is the proper visa for most people and doesn't have ANY of the requirements, just proof that you are over 50 and proof of funds, that's it.
You can't use that until year 2. For the first 1-year extension immigration only accepts 800k in your Thai bank account or embassy certified income. The US embassy doesn't do that anymore, so it's only the 800k. Then during the first year as long as you get an international deposit of at least 65,000 baht every single calendar month for the 12 months before you apply for next extension, you can use that instead of the bank balance. But you need to keep your balance up to meet this year's extension requirement which is 800k for 2 months before, 3 months after extension, and then never below 400,000
You've only got one chance. You need to go to your immigration office and ask them if they support the "visiting Thai family" extension. This is a 60-day extension that might be available to you because you have a Thai wife.
If it's available, apply for this and it should give you time for your money to be in the account long enough. You need to check what the requirements are if they will allow you to apply, because I'm not sure if your marriage has to be registered in Thailand or not and that can be quite a process if yours isn't already registered.
Normally entering on a different entry type forfeits whatever you had. You would have needed to argue this at the airport to be stamped back in with your previous extension. Now that you stamped in without it, it's 99% gone.
But I'm not sure why you say it's a costly process to start all over. 2000 baht at immigration to convert to non-O. Wait 60 days then 1900 baht to apply for 1-year extension.