What are the requirements for the 65,000 THB monthly deposit for a Non O retirement Visa renewal if my nationality does not have a verified pension letter?

If you hold a NZ passport you’ll be able to get a affidavit letter regarding income.

𝗙𝗶𝗿𝘀𝘁 𝗶𝘀 𝗶𝘁 𝗰𝗼𝗿𝗿𝗲𝗰𝘁 𝘁𝗵𝗮𝘁 𝘁𝗵𝗲 𝗱𝗲𝗽𝗼𝘀𝗶𝘁 𝗺𝗲𝘁𝗵𝗼𝗱 𝗶𝘀 𝗼𝗻𝗹𝘆 𝗮𝘃𝗮𝗹𝗶𝗮𝗯𝗶𝗹𝗲 𝘄𝗵𝗲𝗿𝗲 𝘆𝗼𝘂𝗿 𝗘𝗺𝗯𝗮𝘀𝘀𝘆 𝘄𝗶𝗹𝗹 𝗻𝗼𝘁 𝘃𝗲𝗿𝗶𝗳𝘆 𝘆𝗼𝘂𝗿 𝗽𝗲𝗻𝘀𝗶𝗼𝗻?

Nope that is not correct, and believe me far more than those 3 countries embassies here don't issue that letter..

The monthly deposit method is available for any nationality and just because you happen to come from a country whose embassy here does issue the income affidavit doesn't mean you can't use monthly income by international transfer as the means to meet the requirements.

I know several people who live up country, whose embassies DO issue the income affidavit BUT who don't want to slog down to bangkok to get it so meet the requirements by monthly transfer instead

The income affidavit from the country your passport is from is the only one accepted for monthly income method by embassy letter.

Doesn't matter in the least where you live, matters what country your passport is from and if you want to use the income letter you get it from that embassy here

BUT

as I said there is no rule that says you HAVE to use the income letter if your embassy issues it.

As long as you have a minimum of 65K baht a month transferred in from abroad, each month, every month, for the previous 12 months before you apply for the extension (and all those transfers code in your bank book as international origin) you can use that for proof of funds