Seems Pius XII would've understood it had to be in union with all of the bishops to meet the demand of the Blessed Virgin. Are they commenting here simply on the fact that he did Consecrate Russia, but did so in a private manner, or do they think this fulfilled the request? Strange. The Frere Michel book is a great book.
Have you ever looked into the Dimond's research on the subject? It's well done with many references.
They explain the following....
MHFMBut didn’t Our Lady promise that Russia would be consecrated in union with all the bishops of the world? No! This is a key point. Our Lady requested that Russia be consecrated in union with all the bishops of the world, but on July 13 she only promised that “In the end my Immaculate Heart will triumph. The Holy Father will consecrate Russia to me, and it will be converted and a certain period of peace will be granted to the world.” Notice that Our Lady didn’t promise: “The Holy Father and all the bishops will consecrate Russia to me…” Further, heaven revealed that the actual fulfillment of the consecration of Russia would not be fully in accord with heaven’s original wishes; for instance, it would be “late”.
They further go on to state...
MHFM
HE WILL DO THE CONSECRATION, BUT IT WILL BE “LATE” – FITS POPE PIUS XII
It is certain that Pope Pius XI failed to consecrate Russia to Our Lady’s Immaculate Heart. Pope Pius XII also failed to do so for many years, but (as we saw) he finally did consecrate Russia in 1952.
Our Lord to Sister Lucy, Summer, 1931: “Like the King of France they will repent and do it, but it will be late. Russia will have already spread its errors throughout the world provoking wars and persecutions against the Church: the Holy Father will have much to suffer.” (quoted in The Whole Truth About Fatima, Vol. 2, pp. 543-544)
It’s clear that, as most commentators agree, Our Lord’s words “They” will repent and do it apply to the line of popes – just as popes in encyclicals refer to themselves as “We.” (“They” cannot refer to the pope and all the bishops, because all the bishops did not delay the request and therefore do not need to repent of delaying it.)
That Pope Pius XII was the one who did it, but “late,” makes perfect sense.
First, Pope Pius XII consecrated the world to the Immaculate Heart of Mary in 1942. Ten years later, however, he “repented and did it” by specifically consecrating Russia.
I don't know... I think it's very interesting, and it makes sense to me.