Lewy may have been briefed by someone who told him of the NCIS report residing in “Office of the Director, Judge Advocate Division, Headquarters USMC, Winter Soldier Investigation files”.
Lewy could have taken notes as to what to expect when he read the actual report himself, and then forgot that that he didn’t read it himself. As he says now, he can’t recall.
No dishonesty if it happened that way, just a mistake.
Lewy’s account of the NCIS report has the feel of a brief summary: e.g., no names of individual WSI witnesses.
On your other point:
Lewy may have been briefed by someone who told him of the NCIS report residing in Office of the Director, Judge Advocate Division, Headquarters USMC, Winter Soldier Investigation files.
If that were the case, it would have been indicated by a prefatory comment such as "Conversation with. . ." or "Communication with. . ." or something like that. The way he cites it is a citation format for a government document. There is nothing to indicate otherwise in his book, it's only the much later interview that was spun to suggest the possibility of an oral briefing, but what he recorded in his book when he wrote it is very clearly referencing a document. A historian used to working with government documents looking at this note would assume a document was intended--I have seen a very similar format used for citing FBI files, for instance. That a document is indicated by this wording is also implied by the general comments in Lewy's preface and at the beginning of his footnotes where he discusses his sources. His preface says, "Scholars interested in the archival location of particular documents should consult the Note on Military Records at the back of the book", and the comments there pertain to the format used in the footnote we're discussing.
The Note on the Military Records also has another item I noticed which may be relevant to our discussion:
Records of general courts-martial and of special courts-martial resulting in a bad conduct discharge involving U.S. military tried and convicted in Vietnam are held at the Washington National Records Center. Access to Army cases is arranged through the U.S. Army Judiciary, Falls Church, Virginia. Access to Marine Corps cases is through the Military Law Branch, USMC Office of the Judge Advocate General. .. Investigative files on war crimes are held at the respective Offices of the Judge Advocates General, but probably are no longer accessible due to Privacy Act constraints.
Lewy's preface indicates he began writing his book around 1972, and his access to documents was facilitated by an Executive Order issued on March 8, 1972, which permitted the military to give qualified researchers discretionary access to classified files. The Privacy Act Lewy mentions went into effect in 1974. Perhaps that is part of the problem with accessing these records today?
Finally, Lewy's preface indicates his research was assisted by Major W. Hays Parks of the staff of the Judge Advocates General's School at Charlottesville, Virginia, Dr. Charles MacDonald and Vincent Demma of the Vietnam project of the U.S. Army Center of Military History, and John Henry Hatcher, formerly chief archivist of Vietnam records, U.S. army, who is credited with helping cut through bureacratic red-tape. Perhaps some of these individuals or those who knew them could be of assistance to researchers today.