As long as he meets the requirements for an in-country Non-O visa and following 1-year extension based on being married to a Thai national, it is possible. Those requirements are immigration office-specific. He needs to check with the local Immigration office where they are going g to live for detailed requirements.
This link is general information for an initial in-country non-O visa and the attached is for a following 1-year extension.
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/6.FOR-PROVIDING-SUPPORT-TO-OR-BEING-A-DEPENDANT-OF-A-THAI-CITIZEN-SPOUSE-VISA-NON-O.pdf