According to his biographical information he considered himself an Orthodox Anglican until his death. If you want to make him a Roman Catholic, be my guest. To base C. S. Lewis’ conversion to Catholicism on the Screwtapes is laughable. By that process you could make Charles Manson into a convert to Catholicism. I guess it never occurred to you that you don't have to be Roman Catholic to have a profound faith or a brain.
'Scuse me, did I mention
Screwtape? Completely inapplicable here. Lewis said writing it gave him spiritual cramp because he was trying to think like the Enemy. I referred you to two specific citations in two specific works in which Lewis affirmed two points of doctrine generally considered Catholic.
And, when you say "Orthodox Anglican", exactly what do you mean? You have to understand that Anglicanism encompasses everything from the most pared-down plain Puritanism to Catholic-in-all-but-name.
I know because I used to be one, and I was a serious student of Anglican thought and philosophy. When we converted to Catholicism, we found that the only matters on which there was need for a change in affirmation were two: the validity of Anglican Orders and the supremacy of the Pope.
Admittedly we were at the "high" end of the spectrum, but so was Lewis.