No, he didn't give his answer re: sedevacantism then because he did not expel them from his Society for sedevacantism. Here is the Letter of the Nine to ABL that precipitated the expulsion:
http://www.traditionalmass.org/articles/article.php?id=48
Note that of the issues presented, sedevacantism wasn't even mentioned. In addition, not all of the Nine even held the position at the time (although eventually ended up doing so).
When they were expelled, they all immediately started either their own or joint sede chapels. We all know that the sedes, for whatever reason, try to say their expulsion was due to something other than sedeism, but that is not so because sedeism was the root cause of their disobedience, which
disobedience to their superior is the official reason they were expelled. Ask any current SSPX priest who was around in those days, they will all tell you the same thing - that the nine were expelled on account of sedevacantism. They wholly rejected the most fundamental of all Catholic principles, same as all dogmatic sedes still do and always will.
Snip:
So what does St. Thomas Aquinas say about the authority in the Church? When can we refuse something from the authority of the Church?
Principle: Only when the Faith is in question.
Only in this case. Not in other cases... only when the Faith is in question... and that is found in the
Summa Theologica (II II Q.33, a.4, ad 2m): St. Thomas' answer is that we cannot resist to the authority; we must obey:
- "Sciendum tamen est quod ubi immineret periculum fidei." Periculum fidei, i.e., the danger to our faith...
- "etiam publice essent praelate a subditis arguendi.", i.e., the subject can be opposed to the authority if the Faith is in question ("periculum fidei");
- "Unde et Paulus, qui erat subditus Petro, propter imminens periculum scandali circa fidem, Petrum publice arguit," i.e., St. Paul opposed St. Peter because it was a danger for the Faith (cf. Galatians 2:11).
That is the principle (of St. Thomas), and I cannot harbor another motive to resist the pope… it is very serious to be opposed to the pope, and to the Church. It is very serious, and if we think that we must do that, we must do it (resist the Holy Father) only to preserve our Faith, and not for any other motive.
We must now do an application of the principle. For me I think that the liturgical reform of Pope John XXIII has nothing against the Faith. You can take the
Pontificale, the
Rituale, the Breviary, the Roman Missal, and… what is in these books of Pope John XXIII that is against the Faith? Nothing! And so [in an urgent tone]: ...I cannot refuse this book (of Pope John), because he is the pope, and the pope gave me this book (and I must obey).
It is quite another thing with the reform of Pope Paul VI… in this book of reform of Pope Paul VI is a very grave danger to my Faith... it is precisely
Periculum Fidei. So I refuse it, because ecuмenism is the idea and motive of this reform… and this ecuмenism... they say themselves, Pope Paul VI, Bugnini, etc., all say the motive of their reform is ecuмenism, and this ecuмenism takes away all (Catholic) things which are displeasing to the Protestant......