OK, so let me get this straight. Someone doesn't know Christ but lives a good life is already saved. So Christ tells His apostles to go out and proclaim His gospel of salvation. They go out and tell these people that if they don't accept Christ they will now be sent to hell. The people say no we already are going to heaven so they reject this story. Now they are going to hell. Did I get the gist of that?
If they were already going to heaven, then by hearing about Jesus and rejecting Him, now they're going to hell?
So why would anyone go out and tell them about Jesus then?
How is that doing them any favors?
FWIW, rejecting the false teachings and religion of Catholicism is NOT rejecting Jesus Christ.
Rejecting false teaching about Mary does not equate to rejecting Jesus Christ.
Rejecting the self-proclaimed infallibility of the pope and magisterium is not rejecting Jesus.
One can certainly loved Jesus and follow Him without loving and following the false system of man-made teachings that have sprung up in His name no matter who claims to be speaking for Him, Catholics, Mormons, JW's, Pentecostals, whoever......
Not everyone who claims to be from God is. That's why God told us in Scripture to test the spirits and see if they are from God or not and the measure we use is the Word of God.