Yet again, you cite texts deceptively. Are you intending to lie?
You say that LOTR shows the "Fall" in characters "surrendering to temptation." So whenever someone takes something tempting—it becomes a Christian text? You are truly desperate.
In the letter to Camilla Unwin, Tolkien does not prostylize Christianity in any way. He refers to God as a "a Creator-Designer, a Mind to which our minds are akin”—and encourages some kind of connection this consciousness. He does not discuss the "church" or Jesus. It is therefore not Christian.
Tolkien's late-life letters to his grandson, meant to model filial piety to his personal progeny and not meant to be read by history, are not evidence of lifelong practice of religion or full views--a point made with evidence in Raymond Edwards' biography.
https://www.scribd.com/book/481662882/Tolkien
Neither is Humphrey Carpenter's biography acceptable as a factual record, as he repeatedly warned it was merely the family narrative imposed on him.
And none of this speaks to LOTR, conceived decades prior in a period about which little is known, except that Tolkien said he'd all but apostatized.
You don't acknowledge Tolkien's clear belief in reincarnation, and don't deal with his 1954 statement that no theologian knows what happens in the afterlife. He was an agnostic.
Please just stop lying.