The Gospels are from eyewitnesses who documented their time with Jesus. There is scripture that states the Holy Spirit will help them along and I'm certain they had visions that helped them remember so that they would thoroughly capture all the details. The Gospels are 100% verifiable accounts of Jesus and that makes the scripture true and Jesus the Son of God who came to the world to free us from sin.Is the information in the Gospels true? Were just the names changed?
The Gospels were misnamed to commit a fraud on the church, so yes I found some modifications that were made to build a story about Peter being in charge of the church. The edit with the most impact is the one found in Matthew 16:18, and with that you have a major reason for changing the names of the authors. With Nicodemus as the author, he wasn't there to hear that and he didn't copy it from James because that comment is only mentioned in Matthew. I hope you find that very strange that the verse the Catholic Church is built on was only mentioned in one Gospel - the verses with the widest impact on the church!!!
You should also find it strange that there are only two sections of missing scripture and one of these is just after the Pharisees challenged Nicodemus to investigate Jesus to see if he is the Messiah. I wonder what came after that? That brings up the biggest point - a few verses were changed to support Peter, but what everyone should be asking is, "What about everything that's missing?"