Unfortunately, your question is an impossible question to answer, despite the valliant effort by some of the previous posts. The fact that these supposedly selfless, moral, charitable people have heard the Christian message and rejected it makes it impossible for them to enter heaven no matter what I do for them.
"Jesus said to him, 'I am the way, the truth, and the life. NO ONE comes to the Father except through me.'" (emphasis added)
If they rejected Christ and the sacrifice that he made for them, they also rejected God and will NEVER have a place in heaven no matter what sacrifice I would be willing to make.