I think that PiusXII's Musicae Sacrae Disciplina made a change in the definitions involved here.
IIRC, the Pope tightened the definition of orders to exclude those singing in the choir--meaning that using women in your basic parish choir was OK (blessing, after the fact, the common practice.)
That change was applied to 'acolytes,' changing the previous "all-male" requirement and effectively downgrading them to 'lay ministers.'
IOW, your use of the term "ministry" is inaccurate, and your conclusions are not within canonical definitions.
Further, there's no "doctrine" involved in the question anymore.
Your corrections, per current Church teaching are correct. However, each individual priest can decide whether or not he wants females in the schola or not. Some traddie communities do. Some do not.
I am aware the Pius XII made this change. I believe, however, it is still within my rights to argue as to the prudence or imprudence of allowing women to sing; however, of course, this would not be binding in any way.
I believe that the correct term to be used for laymen is "apostolate," not ministries, at least according to the Second Vatican Council's Decree on the Apostolate of the Laity. I believe the term "minister" and "ministry" is reserved to the ordained, per a document issued by the Joseph Cardinal Ratzinger.
Where it is impossible to have schools of singers or where there are not enough choir boys, it is allowed that "a group of men and women or girls, located in a place outside the sanctuary set apart for the exclusive use of this group, can sing the liturgical texts at Solemn Mass, as long as the men are completely separated from the women and girls and everything unbecoming is avoided. The Ordinary is bound in conscience in this matter." (Musicae Sacrae, 74)
I think the "outside the sanctuary" is the important bit here. And it would seem that as late as Pius XII the all-male choir was still viewed as the ideal.