1. I didn't hear the story second hand from the internet.
2. There are no "real" documents. At most they might put 800,000 in your account and withdraw it immediately. The money is certainly not there for the required 2 or 12 months. So, either:
(a) the letter that says that you have complied with the requirements is missing (and the IO has been bribed to overlook that fact), or
(b) the letter is a forgery, or
(c) the letter is misrepresenting the facts.
It's ridiculous to maintain the assertion that such a visa or extension has not been obtained under false pretenses when you have not in fact complied with the requirements.
Avoiding OA gives you the freedom to choose whatever heath insurance policy is best for you. (And you don't have to worry about policy dates aligning with visa extension dates.)
It doesn't happen often, but one time I know that immigration went right through one agent's client list and deported them all and gave them five year bans.
A tourist visa is 60 days, and that is way more than enough to open a bank account and fill in the visa application form. There is absolutely no need to add an extra 30 days as a matter of course. You presented it as *the* way to do it. It is merely an option (and one that is highly unlikely to be needed).
OA visa is normally not as good as an O-visa due to restrictive health insurance rules (plus there's the need to get a medical check and a police clearance report)>
Someone over 50 married to a Thai basically has six options (apart from Elite visa, etc):
Basically, you need the account in the country where you apply. As the UK offers non-o (retirement) visas, it's best to do it there. Do not get an OA visa.
You can get a lot of rejections, but in the end, everyone manages to do it. Stick with Bangkok Bank, Kasikorn, or Krungsri. Go to bigger branches, e.g. in malls. Take your gf with you.