In a new video, the group asserts that the "ambassador's deputy" briefed Clinton on the morning of the incident. Crossroads says Clinton knew it was terrorism, but continued to push the message that an Internet video and protests led to the attack.
"A 22-year-old career diplomatic veteran, intimidated for daring to blow the whistle, all under Hillary Clinton's watch. How could this happen? Why did she blame a video? And was she part of a cover-up?" says a narrator in the video.
Hicks testified that Clinton called him at 2 a.m. on the night of the attacks. He also reported her chief of staff, Cheryl Mills, subsequently criticized him for talking to a visiting member of Congress about the attacks.
Speaking to the House Oversight and Government Reform Committee, Hicks said United Nations Ambassador Susan Rice’s remarks blaming the attack on an anti-Islam film were shocking and offended the Libyan government.
He said the comments frustrated Libyan officials, causing them to purposefully block for 17 days the FBI from entering the country to investigate the attack.
“I was stunned, my jaw dropped and I was embarrassed,” Hicks said of Rice’s remarks.
Hicks, along with two other government whistle-blowers, delivered stark criticism of the administration's handling of the attack, but none of the witnesses offered evidence that Clinton was complicit in the security failures.
Although the Crossroads video mentions other administration officials, including Rice, it primarily focuses on Clinton, who has been continuously mentioned as a possible 2016 Democratic presidential candidate.
The former secretary of State is facing new calls to return to Capitol Hill to testify again.
In an interview with USA Today, Sen. Lindsey Graham (R-S.C.) said Clinton should be compelled to testify under subpoena if she doesn’t return to Capitol Hill willingly.
"I hope she would come back without that, but yes," Graham told the newspaper.
—Jordy Yager and Sheldon Alberts contributed.