@Tullio ******
that is a bad understanding of it, It does not work that way sadly π
His wife FIRST needs to get OFF the visa exempt/tourist visa entry and apply for a 90 day Non-O visa based on "trailing spouse". That is not issued inside thailand to a spouse of someone on a "retirement visa" (Non-O visa/extension)
That's the problem, and anything as far as how the process works AFTER she has her Non-O is unfortunately not relevant to this current situation (with him getting a non-O to come here)