[aMorePerfectUnion]

If they were not saints before they died - like every single believer is declared a saint by God - there is nothing that can make them saints now.

[Salvation]

This is how the Catholic Church does it. Can't you just accept it?

How does the Roman Catholic Church determine sainthood? [Catholic Caucus]
How Many Miracles are Required to Canonize a Saint?
Saints [Catholic, Orthodox, Open]
SAINTHOOD 101: Rules for Becoming a Saint [Catholic Caucus]
The Process of Becoming a Saint (Canonization) [Catholic Caucus]
Pope Lists Criteria for Causes of Canonization