rubbish, the MFA is responsible for Embassy issued visas and Immigration responsible for entries and extensions. Completely different government departments who actually don’t talk very well to each other. The MFA have nothing to do with extensions.
the government officer responsible for issuing the visa in not the same as the government officer responsible for issuing the extension. Nobody knows what the requirements or cost will be as the responsible government officer is silent on the issue.
Please show me the requirements for a soft power DTV. What? You can’t? Is that because every Thai Embassy sets their own requirements? Every Embassy criteria is unique to them. There are ED visas available for Muay Thai but the DTV is being issued for 2 week courses. Suggest you research more before making sweeping statements.