That was the explanation in the official
Relatio of Bishop Gasser. Namely, the term
definit must be clearly expressed - as far as doctrinal matters go, anyway
(1) So what if he quotes several Fathers to evince what their
practice was? How does that make it a doctrine?
(2) Please clearly cite where Vigilius “teaches” that the Church cannot judge one contrary to his status at death? IIRC, he was just giving examples of the
practice of those that went before, stating that he did not dare to do it, so others should not do it as well
A decision that still awaited his confirmation.

Your interpretation that the fathers went ahead DESPITE Pope Vigilius does not align with the text of the Sentence. Here was the course of events:
(1) Vigilius issues the Judicatum then withdraws it, when the West and other Eastern bishops protested;
(2) Vigilius initiates a Council, wanting it in Italy or Sicily to ensure equal representation. But Julian convened it in the East w/ a preponderance of bishops under his control.
(3) Vigilius refused to attend, but was forced by the Emperor to do so.
(4) Vigilius did not participate at the Council, but promised to make a separate judgment against the matters in the 3 chapters.
(5) Vigilius made his judgment in the Consitutum (signed w/ some other bishops), affirming the orthodox doctrine of the Church, while condemning the heterodox doctrines in the 3 chapters, but refused to condemn any person and the letter of Ibas.
(6)
The Constitutum was not made public to the Council because the Emperor refused to do so.
(7) Thus, based on Vigilius’ promise in (4) above, the last impression of the Council fathers was that Vigilius intended to condemn the 3 Chapters, proceeding w/ the Sentence
in good faith that they were one with their head bishop. Indeed, the last mention of Vigilius in the Sentence was his promise to make a separate judgment on the matter.
(8) So the Councils fathers were simply waiting for the separate judgment of their head bishop - in effect, his confirmation.
Ummm. That’s what I said.:shrug
(1) A "rival synod - an imaginative claim. What support is there for it? Did the other bishops condemn this so-called “rival synod” in its Sentence? Were the other bishops even aware that a “rival synod” was being held? The idea is rather ridiculous.
(2) Thanks for the quote. It’s interesting that no anathema was made, as was wont for such matters in those days. The issue was not one of doctrine, contrary to your earlier claim.
(3) Since it was Pope Vigilius’ intention to call a council in the first place, then that means he intended the matter to be judged by a council composed of bishops from everywhere, not by himself. The effective authority here was the formal collegial authority of a council, not the personal authority of the Pope. That his brother bishops corrected their head bishop on this matter is NO big thing. It is a very natural procedure in the principle of collegiality - sometimes it is the head bishop who must accept correction; other times it is other bishops who must accept correction.
(4) In any case, this was not really a contest between the formal personal authority of the Pope, on the one hand, and the formal collegial authority of the Pope with his brother bishops, on the other (for even the Eastern bishops thought they were giving a Sentence in consensus with an expected judgment by the Pope). Rather this was a contest between the Emperor and the Pope.
Catholic Canon law recognizes that a decree must be published before it is effective. The Constitutum was never published - it was not effective.
Blessings,
Marduk