I thought the label “Republican” is not affixed unless one adheres to certain standards. The party as a whole must enunciate those standards and hold candidates accountable both before and during their hold of office. Have you tried recalling? All the options are open, but I would caution against diluting effect of third party.
He’s going to support the primary challengers of people who went against him.
There is no such thing as “Recalling” ... at least for U.S. Senators and Congressmen.