Could Morton Smith's Clement of Alexandria and a Secret Gospel of Mark Have Fallen Out of Copyright?

The book was published in 1973 of course and I found an entry for the book in the Library of Congress's Catalog of Copyright Entries. Third Series: 1973: Title Index. The entry I believe on page 3916 for July - December assigns it the number A446560 (the print is unclear).  The copyright would have come up on 2001.  When I go to the copyright website of the Library of Congress, I see a number of books of Morton Smith listed but not Clement of Alexandria and a Secret Gospel of Mark:

#	Name (NALL) <	Full Title	Copyright Number	Date
[ 1 ]	Smith, Morton	Greek magical papyri in translation : including the Demotic spells / edited by Hans Dieter Betz.	TX0003514124	1992
[ 2 ]	Smith, Morton	Telecommunications : G-FY : TCM 420 : faculty curriculum / contributors, Craig Bergeron, Morton Smith.	TX0004578366	1997
[ 3 ]	Smith, Morton	Language-enriched exercise for clients with Alzheimer's disease / Sharon Arkin with contributing author Morton Smith.	TX0006122821	2005
[ 4 ]	Smith, Morton	Ancient Greeks. By Morton Smith.	RE0000409757	1960
[ 5 ]	Smith, Morton	Heros and gods; spiritual biographies in antiquity. By Moses Hadas & Morton Smith.	RE0000647119	1965
[ 6 ]	Smith, Morton, 1915-	Jesus the magician / Morton Smith.	TX0000073652	1978
[ 7 ]	Smith, Morton, 1915-	Hope and history, an exploration / Morton Smith.	TX0000444590	1980
[ 8 ]	Smith, Morton, 1915-	What the Bible really says / edited by Morton Smith and R. Joseph Hoffmann.	TX0002618089	1989
[ 9 ]	Smith, Morton, 1915-	Hope and history, an exploration. By Morton Smith.	TX0000514005	1980
[ 10 ]	Smith, Morton, 1930-	Cartoon treasury of Morton Smith.	TX0001929454	1986
[ 11 ]	Smith, Morton, 1930-	Idyll, portraits, and landscapes / by Morton Smith.	TX0001931162	1986
[ 12 ]	Smith, Morton, 1930-	General Mark Clark drops by Fort Knox, my first day in the Army.	VA0001034562	2000
[ 13 ]	Smith, Morton Charles	Principles of physical metallurgy. By Morton Charles Smith.	RE0000217147	1956
[ 14 ]	Smith, Morton Charles	Alloy series in physical metallurgy. By Morton Charles Smith.	RE0000217146	1956
[ 15 ]	Smith, Morton D.	Map of the Old Spanish Trail.	VA0000119799	1981
[ 16 ]	Smith, Morton D.	Muleteer.	TX0001017851	1981
[ 17 ]	Smith, Morton D.	Muleteer.	TX0001003970	1981
[ 18 ]	Smith, Morton E.	Case studies in ophthalmology for medical students : instructor manual / Mark J. Mannis, Morton E. Smith.	TX0001989390	1986
[ 19 ]	Smith, Morton E.	Basic science, refraction, and pathology / Morton E. Smith, Marilyn C. Kincaid, Constance E. West.	TX0005539555	2002
[ 20 ]	Smith, Morton E.	Diseases of the conjunctiva, cornea, and sclera--Ocular trauma : accidental and surgical / Morton E. Smith.	PA0000091871	1980
[ 21 ]	Smith, Morton E.	Case studies in ophthalmology for medical students : student manual / Mark J. Mannis, Morton E. Smith.	TX0002027451	1986
[ 22 ]	Smith, Morton E.	Ocular pathology / Myron Yanoff, Ben S. Fine ; foreword by Morton E. Smith.	TX0005534866	2002
[ 23 ]	Smith, Morton E., 1934-	Case studies in ophthalmology for medical students : instructor manual / Mark J. Mannis, Morton E. Smith.	TX0003592671	1993
[ 24 ]	Smith, Morton Mott	Principles of mechanics simply explained. By Morton Mott-Smith.	RE0000561958	1963
[ 25 ]	Smith, Morton P.	Hopalong Cassidy enters & 43 other titles; motion pictures.	V2487P152	1989

When I do a Title search for 'Clement of Alexandria' I get the following:

#	Title <	Full Title	Copyright Number	Date
[ 1 ]	Clement of Alexandria and the Valentinian gnostics / Judith L. Kovacs.	Clement of Alexandria and the Valentinian gnostics / Judith L. Kovacs.	TX0000285272	1979
[ 2 ]	Clement, of Alexandria, ca. 150 - ca. 215	Stromateis : bk. 1-3 / Clement of Alexandria ; translated by John Ferguson.	TX0003400597	1992
[ 3 ]	Clement of Alexandria, Christ the Educator.	Clement of Alexandria, Christ the Educator. Translated from Latin & Greek by Simon P. Wood.	RE0000121289	1954

I tried to search for this book a hundred different ways in the catalog all of which gave me hope that the book might now be in the public domain. My hopes were ultimately dashed by noticing this at another page at copyright.gov:

Any work published or registered before January 1, 1964, must have been renewed by an application for registration in the 28th year following the original date of publication or
registration to continue its term of protection for another 28 years. However, copyrights in works registered or published between January 1, 1964, and December 31, 1977, have an automatic renewal for a full 95-year term of protection. Although the period of protection is automatically renewed, a renewal application may be submitted anyway. If the work in question is more than 27 years old and less than 95 years old, a renewal registration consists of all the following:

• the title and author(s) of the original work
• the renewal claimant or claimants
• the date on which the second term of protection commenced, and
• the renewal registration number, which is the letter R or the letters RE followed by from one to six digits

That would seem to close the door on the possibility of transcribing large portions of Morton Smith's book at my blog. And so we finally see the real reason why Morton Smith's research will ultimately fade from the world - preserved in the wrong format!