Everything keeps coming back to the Atlantic article.
However I did find one that seems to give more information:
https://beelineblogger.blogspot.com/2013/06/the-longest-day.html
This article links to an article with a dead link.
Try doing searches on different search engines.
Ive done that and other than finding some references to a few of the men mentioned in the SLA Marshal story (like Taylor), there is nothing identifying all 47 men that hes referenced. If you search free republic, youll see this has been posted in prior years and no one has been able to find out all of the guys referenced by Marshall in that 47 immortals line. Its a shame really. How weve already forgotten these great men.