What do Satanists tell people about Hell? That it's Satan's kingdom? In a sense it is but there is nothing glorious to it and the only thing to look for is fire everywhere. God is the one who created Hell in the beginning as a form of eternal punishment for the ones who walked away from God and gave faith to Satan.
They had more faith in the devil than Jesus Christ who is returning to the earth again. But when? Only God knows.
If Satanists want to avoid Hell and decide to walk away from the devil all they have to do is ask God to forgive them and he will. Everyone in the world are given chances to repent before it's too late.