This ^^ is absurd and makes no sense actually. According to your reasoning, that heretic priest is no more than an atheist layman booted out of the Church to begin with, as such he could no more administer a valid sacrament than you can - because as a heretic he is no longer a member, no longer a Catholic and no longer even a priest. Heresy made him lose it all - to the detriment of the penitent.
In reality, per Trent, the censured priest administers the sacrament just as validly and licitly as a non-censured priest, because once a Catholic priest, always a Catholic priest - "Thou art a priest forever, according to the order of Melchizedek."
Of course he is still a priest. I never said otherwise.
Take the "Orthodox" for example. From your reasoning, they are not Catholic. They are outside the Church. They are not members. From the age of reason they clung to their schism and heresy. You said it yourself, they are not Catholic and are not members of the Church. Yet they can still validly, yet illicitly, confect holy orders and the Eucharist.