At the conclusion of the week of prayer for Christian unity the SSPX District Superior,Italy was unable to say that Vatican Council II itself calls for all Christians to enter the Church for salvation (AG 7) and that Vatican Council II does not contradict the dogma extra ecclesiam nulla salus.
He was unable to say this since he assumes that 'imperfect communion with the Church' (UR 3) is an explicit exception to the dogma extra ecclesiam nulla salus and to Ad Gentes 7.
In a report on the website of the Fraternità Sacerdotale San Pio X the District Superior could not call Pope Francis's attention to the need for all Christians to return to the Catholic Church for salvation according to Vatican Council II. Since, Fr.Pierpaolo Petrucci assumes that the baptism of desire is a known exception to the dogma extra ecclesiam nulla salus. The dead-saved are visible to him. They could also be visible to Pope Francis!
Pope Francis could be making the same error . He too could assume that UR 3 and NA 2 refer to actual cases known in reality in 2014. So now in dialogue and ecumenism the pope assumes that all Christians and non Christians do not need to convert into the Catholic Church for salvation. The SSPX cannot correct him on this point.Since they also assume that all salvation (LG 16,LG 8,UR 3 etc) and condemnation (LG 14 etc) mentioned in Vatican Council II is known not only to God in specific cases - but is also known to us!.
So the SSPX District Superior had to call for an ecumenism of return based on pre-Vatican Council II documents and popes.