I do not cover the death of Jesus (Yeshua/Joshua) in Part 1 as it covers the Israelites and Judahites, However, I do consider the views of the Jews, namely the writings of the first 150 years of the Christian calendar in my Part 2.
I see the questions you raise quite differently: Where did Paul get his ideas? As a member of the Diaspora, what gentile influences caused him to manufacture his models? (Paul is the earliest NT writer we have, apart from maybe Thomas.)
Why should anyone accept Paul's creative imaginings? (Ignoring, of course those writings that have incorrectly been attributed to him.)
No NT writer either saw or heard Jesus. We do not know who wrote the Gospels, so what were their motives?
The Johannine community, for example, wrote some 60 years later. They had been ostracised because of their High Christology.
I suggest that these are the areas of interest -- the creative imaginings.
They were not writing theology. They were writing religious stories. They were not writing literal histories. So ask why they thought like this. Remembering that they were fully convinced that it was all about to end soon with the direct divine intervention of God and the Coming of Jesus in glory. They were writing for their own times.
On top of all that, we need to understand and empathise with the culture of the times, particularly the times they were writing -- apart from Paul, that would be from 70 CE (Mark) to 150 CE (2 Peter).