I am sure you heart is in the right place. But you arguments need a little sharpening up to work.
Being Jewish I neither believe that Jesus was the Messiah or in the concept of "original sin," and I totally accept evolution. However it sounds like you are confusing JW claims for what other religions actually teach as well as stuck reading the Pauline texts from the limited Watchtower perspective.
First off, both Catholicism and Pentecostals believe in the historicity of Adam. The only difference between the two faiths is that Catholicism sees the Genesis account as allegory while Pentecostals generally embrace a Fundamentalist interpretation, reading the Genesis account as literal. So that needs to be adjusted.
Next, the references in 1 Corinthians 15 to Adam introducing "death" into the world does not mean to other Christians what Jehovah's Witnesses claim it does.
The Jewish Annotated New Testament (which employs the NRSV text) has a very hearty footnote to these verses. Being that Paul was Jewish, the reference points out that unlike how the Watchtower interprets these verses, i.e., that Adam passed death to the rest of humanity via our DNA or something of that sort, Paul was likely employing the art of midrash to make a slightly different point.
Midrash is a Jewish form of hermeneutics that plays off the fact that the Hebrew tongue and its idioms are highly terse. Most other languages are not, but Hebrew very much is (meaning that one word can have a variety of subtle meanings). Here Paul seems to be quoting not Scripture but early rabbinical thought from the Second Temple era. Some Jewish sages and rabbis from this era taught that human "mortality" was introduced via Adam's envy, and that the Genesis account was an allegory claiming that humanity has wanted God out of the picture since the beginning (i.e., 'envying' God). The first personification or embodiment of this envy as the "Devil" in a religious text came shortly afterwards as found in Wisdom 2:24, an apocryphal Jewish writing (written around 100 BCE.)
While it is not clear if the text is calling Adam's envy "the Devil" (as Jews generally don't believe there is such a thing as a spirit enemy of God and humans) or if Wisdom is (for the first time in writing) introducing the Devil as a spirit being similar to Christian belief, Paul nevertheless does expand on this ambiguity via midrash in 1 Corinthians.
While Judaism does not teach that we die because we inherited death from Adam as a punishment, Paul via midrash took these elements to play off this illustriously. However, even Paul was not advancing the idea of Original Sin. That is a doctrine the Catholic Church would not introduce until much later. Paul's statement is related only to the Second Temple era theology (and it was not universal among Jews of the time either). The idea that all in Adam are dying as opposed to all in Christ being made alive is not literal, not in the first part anyway. He is merely using the illustration about Adam in arguing his point that resurrection is corporeal, not something that happens when someone dies and goes to heaven (the idea advanced by some that Paul is arguing against). By contrast Jehovah's Witnesses refer to a "heavenly resurrection" which is etymologically incorrect as the term "resurrection" refers only to the reanimation of physical, dead bodies.
All that aside, and as I do not subscribe to Christianity, I don't accept Paul's teaching even here. But what he is actually saying is far different than what you are describing (which seems to be the fault of the JWs never allowing you to learn outside their influence, not yours). Your conclusion has merit, but others outside the Watchtower will simply slice through the details in your argument for the reasons I pointed out. They need to be sound enough to stand up to mainstream theological academia. JW teaching does not.
A footnote: none of the Biblical genealogies are meant to be complete. All of them are based on outside sources, some oral and some written which no longer exist, from which only select names were taken in order to build a narrative in the context in which they occur. Jehovah's Witnesses claim that the Bible is the main source for these records, but the Bible was never the ultimate source for Jewish records, especially genealogical ones, since marriage and business contracts relied upon them. Copies of the Scriptures were never widely available even among the Jews until after the 17th century CE, so it would have been impractical to keep our records in the Bible. One therefore cannot base arguments for or against evolution on them (and remember, I accept the evolutionary model).
