As an independently licensed clinician, as well as a religious, I would be called on to evaluate and issue or deny such certifications as you envision, Mike AA.  And, based on both my own prayerfully informed conscience and in emulation of Saint Pope John XXIII during WWII and the murderous persecution of Jews for whom Roncalli provided baptismal certificates, I would be required by my faith in Christ Jesus to issue a Certificate of Heterosexuality to every cleric and religious who sought one in order to remain in their ministry to the Church and its Faithful.  It is the only way I could remain a true Christian.  I would want to tell the pope - any pope - to come do their own dirty work and face those accused personally and tell them they are not wanted any longer, or at all.