You don’t know whether Jonathan is on the path to conversion. The fact that he’s asking for the intercession of Pope Shenouda of thrice blessed memory is an uplifting sign that he is on the path to Orthodoxy. Things could be a lot worse; he could be venerating the Nestorian blasphemer Leo of Rome, or he could be idolatrating the demented Maximus who taught that the saints become identical to the Lord. Or, if he joined your group, he could be venerating the devoted Freemason, Philaret of Moscow.
This is a good sign that he will eventually accept the faith of the Third Ecumenical Council, which his current sect departed from the faith of in 451AD. Just as the Arian pseudo-councils fall by Nicaea, so too do the Chalcedonian pseudo-councils fall by Ephesus: