You're telling us on one hand that the Catholic is God chosen instrument for salvation and then on the other hand that people can get to heaven without it. Which is it?
Based upon Jesus and Paul's instructions to us, those who are not Christian are excommunicated. It is then up to them and God what happens after that. You wanna reject the Church? Have a nice day. But if you are not Christian, then you are not Christian and cannot be in Christian fellowship.
Those who are Christian ARE the church, the body of Christ. There is no such thing as someone who is not a Christian being excommunicated from the church because they aren't part of the church to begin with.
Not being permitted to be part of fellowship is not equivalent to not being part of the church, the actual body of Christ, or the equivalent to not having salvation.
Salvation is through CHRIST alone, not an organization. Jesus said that HE was the way, the truth and the life and that no man comes to the Father but through Him. He never said it was through the church or a church.
IOW, the Catholic church teaches that anyone outside the Catholic church is going to hell.
No matter how you dress it up, that's essentially what it boils down to and in spite of the fact that the RCC tried to weasel out of directly saying that with its pronouncements in Vatican II, it never really ever directly denied it. And the Catholics on this forum keep reinforcing what we keep saying, that the Catholic church teaches that those outside the church, who are not Roman Catholic, are going to hell.