Hi, Walther,
Not to butt in…

but there could really not have been a ‘discovery’ possible for any of the NT Books. And, this is strictly from a historical or time-line perspective.
As I appreciate the situation, Christ created the foundation for His Chruch on Peter and that was in about 32 or 33AD. Shortly thereafter, Christ was crucified, rose from the dead on the third day and Ascended into Heaven on His Own Power 40 days later on a Thursday. On the following Sunday, Pentecost, the Holy Spirit descended on the Apostles and this is recognized as the Birthday of the Church in 33AD. It would be about another 17 years before the first word of any of the NT Books was written - but, during this time the Apostles were preaching and teaching about Jesus Christ and His Divine Love for all of us.
About shortly before 400AD, three Church Councils had set the Canon of Scripture and it was approved as containing 73 Books (here is an interesting link:
holytrinityparish.net/Links/Our%20Catholic%20Bibles.pdf )
So, the Catholic Church was well established before the Bible (OT & NT) was established. Another way to look at this is that no where in the Bible does Christ tell the Apostles to write anything - they are specifically instructed to preach and baptize - and they set about their task.
Does that help?
God bless
The Catholic Church was founded upon the first Gospel promise:
"I will put enmity between you the serpent] and the woman, and between your offspring and her offspring, he Christ] shall bruise your head Christ’s defeating of death, hell, and the devil by his resurrection from the dead to eternal and total glory], and you shall bruise his heal the innocent and bitter suffering of Christ’s cross of shame]." [Genesis 3:15]
Therefore, while the Church precedes the written form of this promise, it was only by this promise (though initially verbal in its form) that the Church was given life, hope, forgiveness, and salvation.
Is it your contention that when Christ tells the disciples:
"I still have many things to say to you, but you cannot bear them now. When the Spirit of truth comes, he will guide you into all the truth, for he will not speak on his own authority, but whatever he hears he will speak, and he will declare to you the things that are to come. He will glorify me, for he will take what is mine and declare it to you. All that the Father has is mine; therefore I said that he will take what is mine and declare it to you." [John 16:12-15]
that he speaks only of their verbal word and not their written Word, recording those very things spoken (those things necessary for salvation)?
And again, when Christ prays:
"Sanctify them in the truth; you word is truth. As you sent me into the world, so I have sent them into the world. And for their sake I consecrate myself, that they also may be sanctified in the truth.
I do not ask for these only, but also for those who will believe in me through their word, that they may all be one, just as you, Father, are in me, and I in you, that they also may be in us, so that the world may believe that you sent me." [John 17:17-21]
Shall we limit those for whom Christ prays only to those who hear the Apostles verbal word in the Apostles lifetime, or does the text not plainly state that all who will believe, will believe through the Apostles word, necessarily including its written form also?
As Christ Himself writes as to the founding of the Apostles faith and knowledge of the truth:
"For I have given them the words that you gave me, and they have received them and have come to know in truth that I came from you; and they have believed that you sent me." [John 17:8]
Therefore, it is the Word that gives life, whether it be by mouth is of no consequence, as that preached by mouth is necessarily and absolutely confined to that blessed and written Word of God that has been handed down by the Church, through the creation, inspiration, preservation, and providence of the Almighty. That is to say, there can be no separation drawn between the verbal and written form of the Word, but only a distinction drawn between their form of delivery and reception. However, the verbal form, even before the written form was established with certainty by the Church, was always confined and bound to the work, will, and Word of God: hence, their can be nothing added to, subtrated from, or substituted in the Word of God, as the revelation between God and man has been completed in the work and person of Christ, and therefore need not be further extended, but merely preached and offered as the only means of salvation and eternal life.
Sincerely,
WALTHER