There is no quote from St. Augustine in the article that says "God will infallibly provide the Sacrament of Baptism to those who persevere to the end of their lives in a state of justification". St. Augustine said nothing about "people who persevere to the end of their lives in a state of pre-baptismal justification".
LastTrad, you're confusing this with the other thread. This thread is directed at those who hold that St. Augustine's authority proves BoD (all of whom believe in pre-Baptismal justification) ... and thus Xavier's response above. This thread was not attempted to demonstrate the existence of pre-Baptismal justification, but merely conceding its existence for the sake of argument.
In other words: “there’s no such thing as dying in a state of grace without Baptism”.