It is generally thought, that the 3rd Secret of Fatima has to do with the loss of Faith following 1960 - Vat. II and all it brought, including the New Mass, maybe even the devil in the Vatican and taking over the Papacy. We don't know the details for sure.
Maybe it also mentions other punishments, physical punishments upon the world, natural catastrophes, etc.
THERE would be where Our Lady mentioned the New Church, vis-à-vis the Fatima Children.
Would not the Church's sins as in the New Mass and the abuse of the Sacraments, not to mention the changes in the nuns and their religious habits, be the first thing Our Lady would worry about and mention, in this post-Vat. II age, to these New Church sisters, or any New Church sisters? Again, they are engaging in the condemned Modernist Heresy church. If Our Lady is crying for sin to stop and reparation to be made, would she not point out the problem the sisters here are engaging in?
Or do we not think the Novus Ordo Church is sinful, its Mass, sinful? Are we liberals in this respect?
Or, again, did she indeed say something about the diabolical New Church to warn these sisters, but it has been suppressed?