"many contemporary NT scholars,"..."was not uttered by the historic Jesus" The early Ecclesia authenticated the letters written under apostoloic authority. It is foolish for scholars to consider themselves as close as these church leaders. It is not the place of scholars today, whether they are Christian or not. There are some passages which do not appear in "most manuscripts". The passages have been left in the Bible, however, because of the lack of authority to take them out. The content, however, is scriptual, because other passages in the Bible can confirm the teachings. It is entirely possible that the manuscripts that do not have the passage are the manuscripts which are lacking.
Your link ... "Jesus was not interested in moral admonition on the dangers of riches"- Crossan. These reasonings are outside of scripture. I think that appears obvious from that reference. Crossan tries to determine whether this is a parable or not, not whether Jesus said it or not; yet he reasons the same. Using Jewish study methods, you would understand the importance of when a name is mentioned and when a pronoun is mentioned.