Corea is retired army. The database from which the ABMC website was created was produced by a private firm; much of the initial info was provided by ABMC. The firm did an incredibly sloppy job of putting everything together and a great deal of the info is incomplete or incorrect.
This is a common problem on the 'net. A great many websites are produced by buffs, individuals who have a keen interest in their chosen subject, whose emotions or enthusiasm far exceed their knowledge of same. Other individuals, equally lacking in knowledge, information, etc., accept all this as fact, very often regarding the author/producer as an "expert" on the subject.
In regards to family stories. In most cases, they're just that. Stories. During the war, information on casualties was strictly censored. Families were given only the scantiest of information: date, general area, etc. Only the barest information was included in the official Report of Casualty. In cases where comrades wrote the individual's family, giving detailed information, such details were blotted out by the V-Mail Censors.
It's anybody's guess as to how family stories get started. For decades, a relative of mine was said to have been killed during the Normandy Invasion. After years of listening to details that didn't dovetail, I determined that HE HADN'T EVEN ENTERED SERVICE UNTIL A MONTH AFTER D-DAY and had actually been killed in action on the German Border in January 1945 (a sister, to whom I gave a copy of his deceased file, to this day insists he was killed at Normandy).