CathInfo.com

According to this article, there is evidence to support what you say.

In the preparatory phase of Vatican II about 300–500 bishops asked for a definition or formal statement of Marian mєdιαtion and 54 asked for a definition of Mary as co-redemptrix. Pope St. John XXIII, however, made it clear that the Council would not be seeking to proclaim new dogmas.
A draft prepared in advance for the Council spoke of Mary as co-redemptrix, but the fathers of Vatican II decided to omit the term from what would become chapter VIII of Lumen gentium. The term, however was not rejected because it was false. In the praenotanda or explanatory note that accompanied the first Marian schema of 1962, we are told that: “Certain terms and expressions used by Roman Pontiffs have been omitted, which, although most true in themselves (in se verissima), may be difficult for the separated brethren (as in the case of the Protestants) to understand. Among such words the following may be enumerated: ‘Coredemptrix of the human race’ [St. Pius X, Pius XI]; ‘Reparatrix of the whole world’ [Leo XIII] … etc.” (Acta Synodalia Sacrosancti Concilii Oecuмenici Vaticani II, Volumen I, Periodus Prima, Pars IV [Vatican City, 1971], p. 99).
The title co-redemptrix, however, appears in two footnotes of the 1962 schema. Footnote 11 states that ‘the compassion of Mary has a connection with the redemption in such a way that she may rightly be called co-redemptrix’ (Acta Synodalia Sacrosancti Concilii Oecuмenici Vaticani II, Volumen I, Periodus Prima, Pars IV, 1971: 104). In the 1962 schema there was also a lengthy footnote explaining the meaning of terms such as Meditatrix and Coredemptrix as applied to Mary.
The 1962 Marian schema formed the basis for chapter eight of Lumen Gentium, but the final conciliar text did not include the two footnotes on the title co-redemptrix. Even though the title co-redemptrix is not used, some theologians such as Jean Galot, S.J and Georges Cottier, O.P., believe that Lumen Gentium affirms the doctrine of Marian coredemption without using the title (see Galot in La Civilità Cattolica [1994] III: 236-237 and Cottier, in L’Osservatore Romano, June 4, 2002).
https://wherepeteris.com/pope-francis-and-mary-co-redemptrix/

We have had plenty of time since the Council to see how badly this strategy of  not offending Protestants works.  It is not reasonable to continue it.

Consistent with the typology of Jesus as the second Adam who reverses the curse of Adam, Mary is the new Eve.  Jesus is the new Adam, and Mary is the new Eve.  Just as Eve, the first woman, was intimately involved with the first man in the events which led up to the fall of mankind, there is a woman, Mary, who is intimately involved in the events leading up to the Redemption.  Eve disobeyed God and sinned.  Mary obeyed God and never sinned.  Much more could obviously be said on this issue; but the point here is that while Eve’s role with Adam in the events leading up to the original sin was unique and crucial, it was nevertheless the sin of Adam alone which constituted the original sin and effectuated the downfall of mankind.  That’s very clear in Catholic teaching.

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Romans 5:12- “Wherefore as by one man sin entered into this world, and by sin death…”