As TCR points out, it is the height of hypocrisy to use the prudence argument, while for 40 years the SSPX refused to “prudently” follow Rome.

Guess they forgot about this:

https://www.sspxasia.com/Docuмents/Society_of_Saint_Pius_X/Open_Letter_to_the_Priests_of_Campos.htm

X, where might I find Sister Mary Elizabeth's letter?

Fr. Lourenco Fleichman, O.S.B.

Nearly three months ago, Fr. Fleichman posted this letter on the Internet to manifest his disapproval of the agreement then being planned between the Vatican and the priests of the diocese of Campos, Brazil. The Accord was subsequently approved by the Priestly Union of St. John Baptist Mary Vianney with the approbation of Pope John Paul II, and sealed in a ceremony of reconciliation in the Cathedral of Campos, officiated by Cardinal Castrillon Hoyos in the presence of Bishop Rangel and his priests, Bishop Guimaraes, the diocesan bishop, his Novus Ordo priests, the Apostolic Nuncio, and Novus Ordo bishops from surrounding dioceses, on January 18, 2002.

Niteroi, October 30, 2001 Most Reverend Bishop Rangel and very dear Fathers: I am not the best placed person for writing you this letter. I do not think that I shall obtain from you the assent that you declined to the bishops of the Society (of Saint Pius X), Bishop Fellay and Bishop de Galarreta, when they tried to show you the fearful damage that these accords between you and the Vatican could inflict on the Church and on the fight for the "survival of Tradition." Nevertheless, I have a very serious reason for writing you about this, and I do so with the advice and approval of Bishop Fellay himself. The reason is that several of our faithful at Niteroi and Rio come from villages you are responsible for, and they have always held the "Campos Fathers" in the highest esteem and reverence. Now they cannot manage to understand the reason for an agreement (with Rome) made separately from the Society of Saint Pius X and which, moreover, goes against the counsel and advice of the Society bishops. Another reason that encourages me to write you is the experience I lived through in 1988 at Barroux, when Dom Gerard Calvet too wanted to make a deal with the Vatican. Here is the first similarity I see between Dom Gerard's attitude and yours: Archbishop Lefebvre had just refused an agreement because he had not been able to perceive in the Vatican's intentions the guarantees that would be necessary to assure the survival of Catholic Tradition. Dom Gerard, placing the particular interests of his monastery above the Church's good, accepted a separation from Archbishop Lefebvre in order to "normalize" his juridical and canonical status, thereby letting fall the sword of combat. Today, equally, the Society has just rejected an accord for the same reasons as Archbishop Lefebvre, and you prefer to consider your particular interests and not the common good of the Church. You have grown weary of the daily fight and of being marginalized. But the similarities do not stop there.      When your Fraternity was conducting the current negotiations, I spoke to Fr. Fernando (Rifan) on the phone. He gave me three reasons that he considered sufficient for going ahead and concluding the agreement, even though the Vatican has not agreed to allow the Tridentine Mass: 1) many new persons would rejoin Tradition; 2) we would have a foot in the door of modernist Rome for preaching Tradition; 3) we could still go back to our former position in case we were unduly pressured. These are precisely the same arguments as those of Dom Gerard in 1988; to me, shockingly so. Firstly, because then you knew how to critique Dom Gerard's position, as was so necessary at the time. Second, because today the logical conclusion you are obliged to reach is that Dom Gerard was right! He preceded you by ten years, which obliges you to believe that his assessment then was better than yours. I think that the following affirmations are undeniable: 1) The new people that will join you will not desire to convert to true Tradition. They will come to you because the legal obstacles have been removed, and not for reasons of faith. They will be very sympathetic, but they will not be seeking the whole truth with the doctrinal conviction that leads souls to martyrdom; 2) Being in modernist Rome‑and this is proven‑invariably results in contamination by the guiding principles of Vatican II, administered in homeopathic doses until the fruit falls, as the St. Peter's Fraternity fell; 3) As for going back: who among them has ever returned to his former position? They would rather concelebrate with the Pope than go back. And if they did go back, what would become of the faithful in their parishes? Would they all go back? How many would be entangled over the question of legality? I consider such an attitude reckless; it does not take into account the constancy of the souls that Providence has entrusted to you. You regularize on paper a phony problem of excommunication, and the faithful have only to follow and obey, and then, tomorrow, to about face and retreat with you! I cannot quite see in this the respect for souls the priestly life requires. With regard to the Society of Saint Pius X, I do not understand how you can so obstinately refuse the requests of these bishops who have come to your aid time and time again. First, there was the consecration of Bishop Licinio Rangel, a very courageous act by these bishops, for many could misconstrue this act, as was the case for some. It was by thinking of you and of your faithful that they agreed to the consecration. Also, the seminaries of the Society have always been open to the Campos seminarians; they are received as brothers. And then, when the Society was summoned to negotiate with the Vatican at the beginning of 2001, you were amiably invited to participate (in the meetings of the Society's superiors). They were not obliged to include you, yet, once again, they were generous and fraternal in the fight for Tradition. In view of these facts, by refusing to listen to the supplications of the Society, you incur the terrible burden of betrayal. In that, once again, you match Dom Gerard. Perhaps you do not see the matter thus, but neither can you deny the bishops the right to feel betrayed. And just as Dom Gerard's betrayal caused a terrible drama amongst the French faithful, causing divisions in families and deep disappointment because of this abandonment and weakness, likewise you also, today, are for the Brazilian faithful the cause of the same disappointment and the same divisions. I said in 1988 to Dom Gerard what I repeat to you today: thousands of the faithful anxiously wait for you to confirm them in the Catholic faith, in the combat that divine Providence requires of us, without our succuмbing to fatigue, weakness, or the siren song of legality. What our Lord requires is martyrdom endured drop by drop, and a clear and simple profession of Catholic faith without compromising with the modernists in the Vatican. The Pope, yes; legality, yes; but above all; respond to God's clear call to the combat of the faith. The day the Pope really converts, it will appear more clearly than the light of day. Obviously, it is not by kissing the Koran or by going to pray in a mosque that he manifests this conversion. All the faithful of the chapels of Rio and Niteroi are praying for you, beseeching the Blessed Virgin Mary to turn your hearts to the light of truth. In Christo et Maria, Dom Lourenqo Fleichman, O. S. B.