One cannot change the fact of enrollment through baptism in the Catholic parents Church (e.g., the Latin Church), even through heresy, schism, or apostacy occurred later. The membership from baptism and is perpetual so one does loose membership in their Catholic Church sui iuris by becoming Orthodox, Protestant, or Muslim. Even within the Catholic Churches sui iuris one does not change ascription without the approval of the Apostolic See:
Your citing of Canon 112 absolutely does not address those who have left communion with the Catholic Church, and the caveats you stated do not appear in the canon nor are necessarily implied. The Roman Church does not “own” anyone simply by virtue of baptism when they have left the Latin Church and Catholic communion of their own free will. The meaning of* “autonomous ritual Churches” *in this context is defined and understood solely within the Catholic communion.
When one leaves one state, crosses the state line, and drives into another, the speed limits of the state just left no longer apply. Free will is never trumped, and when the subject leaves the Church through their own free will, the Church does not and cannot exercise “jurisdiction” with regard to law when there is no willful subject. In this case the person has become Orthodox by virtue of formal reception into the Orthodox Church. They are no longer Latin. Their sacramental reality is Orthodox, not Latin.
If Magisterial teaching is to be believed (and hopefully it is) the hierarchal and sacramental validity of the Orthodox Churches are most definitely respected. And thus they would be received back into the Catholic Church as an Orthodox coming into Catholic communion, since they had of their own free will chosen to leave the Latin Church for the Orthodox Church. And thus, assuming again of their own free will they chose (as the Church suggests) to continue worshipping in an Eastern autonomous ritual Church, they would be received into that Church as having come from whatever Orthodox church. To suggest the person has been a “crypto-Latin” the entire time or that all of the sacraments they received in the Orthodox Church “really don’t count, they were always Latin”, is ludicrous and bereft of respect for the efficacy of the sacramental life of the Orthodox.
What is done in a case like this is very simple, namely that when the person is received into the particular Eastern Catholic church, a notation is made to the baptismal registry of the orignal Latin parish church of baptism that (1) so and so received x,y,z sacraments in whatever Orthodox church (since those sacraments are absolutely valid), and (2) the person was received into Sts. Whatever Eastern Catholic Church.
Again, to tell someone that they can’t really be received into a Catholic church until some papers are shared between bishops who really don’t care themselves to be bothered with this is ridiculous. No one should be made to feel like an illegitimate stepchild for wanting to continue to practice their Catholic faith in the same way they have most recently been practicing as Orthodox.