Hate to say it, but I feel O’Bummer is correct on this one. Nullification is not a part of the remedy available to Lutheran Pastors in order to remove their ordination. They have due process procedures in their own rules that must be followed.
If they follow their procedures, then they can do it. But, the process is not retroactive unless the ordination was done through fraudulent representation.
That’s very nice, but these “ministers” are not ordained clergy; they’re merely elementary school teachers. To be a teacher in an LCMS school, one must receive requisite theological training and be “called” by the congregation supporting the school. The ministry of an LCMS teacher is limited to his or her duties as a teacher, much as, say, the duties of an extraordinary minister in the Catholic Church is limited to assisting in distribution of the communion host.