This was a very interesting interview. I've been familiar with Mark's work for about 3 years. When speaking about missing books of the Bible, Mark mentioned the years that nothing was written about Jesus and he was a little off. I believe the silent years were from Jesus teaching in the temple, and I think He was 12. Then when Jesus's ministry started he was about 30.
Mark theorized that there may have been is many as 711 books that vanished because the Holy Spirit may have spoken to many more of His people over the years. I remembered another number that God uses. The number 70. Maybe we are short 4 books? Only time will tell.
It would take some very careful reading for me to believe that new books are in fact Spirit filled. New teachings, as an example, might be: Mary being a valid mediator between God and man would cause me to personality reject them. It's beyond fascinating to to think about what end-time books and relics could be discovered. If anyone here has not watched that interview yet, I think it would be interesting for you.