I don't think anyone should really put a whole bunch of weight into anything one doctor says about memory... especially someone on a promo tour to sell a book.
A director of the NIMH, who I would cite as a responsible, reputable source of information for anything traumatic:
Dr. Thomas Insel, former Director of the National Institute of Mental Health (NIMH) said it best at the 2015 Smithsonian "Future is Here" festival: "In 2015, I can’t tell you -- nor can anyone else -- how the brain functions as an information processing organ. How does it do it? What is meaning, how is it stored, where does it exist, what does it look like in the brain?"
I really wouldn't put much weight into what you're writing here as though memory implantation is possible, or not possible. No doctor knows the answer. It has been done, it has been proven when done. Then there are cases where the same thing has failed.
The brain is complicated...