People who go to heaven are people who have the nature of Jesus in them. People who don't go to heaven are people who are still slaves to their sin nature. Heaven and hell have nothing to do with being good or bad, or what you believe about the universe, though I would add that the nature of God is such that He is everywhere (omnipresent), so it doesn't matter if there is only one universe or bazillions of universes, God is still everywhere. It's what God is. But right understanding comes with time and learning. You won't go to hell because you have a less-then-thorough or less-than-perfect understanding of God.

Will I go to hell if I believe that in this universe, God doesn’t exist, but in another universe he does?