The attack killed Staff Sgt. Bryan C. Black, Staff Sgt. Dustin M. Wright, Staff Sgt. Jeremiah W. Johnson, and Sgt. La David Johnson.
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The video provided new details on how Sgt. Johson died.
Overhead drone video showed that Johnson got separated from his unit while trying to get into a safe position.
His body was found by Nigerian forces under a tree roughly 48 hours later.
However, additional remains were found on Nov. 12.
The video showed an exchange of gunfire and Johnson's body be later recovered.
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Military officials said he was first reported missing hours after the attack.
Myeshia Johnson said she learned her husband was missing in action when military members came to her house.
"They told me there was a massive gunfire and that my husband, as of Oct. 4 was missing," she said. "They didn't know his whereabouts or they didn't know where he was or where to find him. A couple of days later is when they told me he went from missing to killed in action."
On May 10, an investigation by U.S. military officials revealed the mission had been approved without proper authorities and that their unit had not been fully trained for their mission.
After the findings were made public, Defense Secretary James Mattis ordered changes to address the shortfalls in training and authorities uncovered by the report.
U.S. Africa Command has already put in place new training and equipment for U.S. troops serving in western Africa.
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The video also revealed another Nigerian military team initially fired on the group, believing they were ISIS fighters.
The assault lasted less than 60 seconds; no injuries were reported.
CNN and ABC contributed to this post.