Thanks for the question.
I would not give up your passion for Wells good fiction (provided he is not convincing you of anti-Catholic sentiments) but, given that he was so really on the wrong side of the spiritual divide, I would pray for his soul. Our prayers and sacrifices affect souls at any point in history. It is always possible for your prayers now to reach God in the moments leading to his death and provide an outpouring of grace that could affect his salvation. (God is eternal and there is no future in Him).
Imagine that, as a big fan, you get to Heaven to find him thanking you for your prayers. If his fate was sealed in the negative, so to speak, your prayers would be applied to whomever the Lord deems to benefit.
Consider how all those who were saved in the Old Testament were only saved because of the future salvific work of Christ. It is the Paschal mystery that provides the center point of all history for the outpouring of grace to save all mankind, for which we all have a part in helping it to be applied. It's why Mary was conceived Immaculately in advance, and why Abraham, Isaac, Jacob, Moses, and all the Old Testament saints are in Heaven. We don't think linearly, but eternally in Christ, for whom anything is possible.
I pray for my family members who went before me, not knowing their fate. I assume that God will apply prayers to those in Purgatory and for those who needed grace in their dying hour, I pray God will use my prayers for them too. Even better, is having a Mass said. What a great act of charity to do this for someone you have not even met or have blood relations with.
So many souls perish for lack of anyone to pray for them.
So, don't give up on him, just pray for him.