Since day 1, you say?
Just so that we are clear where the disagreement exists,
Let’s sort through everything he said.
1, Christ is the way of salvation. Yes, absolutely.
2, He is present to us in his body, the Church. Yes.
3, He himself asserted necessity of faith and baptism. Yes.
4, He affirmed the necessity of the Church which men enter through baptism, as the door.
No. Absolutely not. Sorry. John the Baptist was Baptizing before the Church was created by Christ. Those who are not Christian, can, in an emergency, baptize.
Christ chose to create the Church, in order that the Word would be spread throughout the world. He also promised that the Gates of Hell would not prevail against the church.
Do I believe that there is one true church? Yes, this is why I am Catholic. I believe that the Catholic church is the Church that Christ founded.
Do I believe that God cannot save without the Church? No. There is plenty of evidence to the contrary. Christ even says to the disciples,
In fact, Christ even says, in Mark 9:38-41
“Teacher,” said John, “we saw someone driving out demons in your name and we told him to stop, because he was not one of us.”
“Do not stop him,” Jesus said. “For no one who does a miracle in my name can in the next moment say anything bad about me, for whoever is not against us is for us. Truly I tell you, anyone who gives you a cup of water in my name because you belong to the Messiah will certainly not lose their reward.