I suggest that Eitan Bendavid familiarize himself with Cassutto’s work on בר×שית (especially the stuff on the Creation and on Noah) Mordechai Breuer’s שיטת ×”×‘×—×™× ×•×ª (פרקי בר×שית is a good place to start), Amnon Bazak’s עד ×”×™×•× ×”×–×” , as well as ×‘×¢×™× ×™ ×-×œ×•×”×™× ×•××“× published by Bet Morasha. The bottom line is that:
On most of the issues raised there is more than a single, authorized view in the ר××©×•× ×™×.
Even on the issues of multiple authorship there are Orthodox voices which accept it in one form or another. The Rambam’s 8th Principle of Faith - תורה מן ×”×©×ž×™× - was not really popularly accepted until the early 19th century, and it’s not even clear that Rambam himself ultimately held by it.
Kol Tuv
Zvi Grumet
Jerusalem, Israel