Very interesting Paul. You obviously have done much more study of the science and philosophy of determinism than I have, so I appreciate this contribution. I don't know that Sapolsky has backtracked and much of what I read in comments about his work is very complimentary suggesting that he has proven his point. Sapolsky is an atheist and Barr is a Christian, so one can see in this discussion the orientation of each. That, in my view, doesn't diminish the arguments at all as those arguments must be weighed based on their strength.
Interesting you are writing about analytic philosophy. Wondering your thoughts on Alvin Plantinga?