if they don't then what would you suggest to help them?
If they don't fear hell? What would I suggest? Nothing. As I said, my job is to share the good news about Jesus, warn people about hell, but the converting is up to the Holy Spirit. As I said, anything I can talk you into, somebody else can talk you out of. But anything the Holy Spirit gives you, it's yours for ever.
I knew about hell from childhood and for some reason I was never afraid. I just did not want to become a Christian because I wanted to live the way I wanted, without rules and without answering to anybody. I was not a bad kid, but neither was I what you might call a good citizen.
My becoming a Christian was gradual, after seeing other good Christians, my parents included, live a life of service to others, selflessness, goodness, peace, joy even in the mist of life problems and suffering, etc. I wanted that peace and that joy. One day I just said a prayer to Jesus and told him that I was willing to stop being selfish and start living as he wanted me to live. Right after that, my life, my personality, my character changed. I wasn't expecting a change like that, but it happened. Those who knew me before and after would tell you that I am a very different, much better person. There is much more I could tell, but I don't have time right now.