By Brian Lowry, CNN

(CNN) -- Oprah Winfrey conducted a sympathetic interview with Wade Robson and James Safechuck, whose allegations of sexual abuse by Michael Jackson provide the foundation of "Leaving Neverland," the stunning four-hour HBO documentary that concluded Monday night.

Winfrey's hour-long special, "After Neverland" -- which aired after part two of the documentary and consisted of interviews with the two men and director Dan Reed -- is perhaps most significant for lending Winfrey's seal of approval to the project.

"For me, this moment transcends Michael Jackson," Winfrey said at the event taped last week, in front of a studio audience that included more than 100 abuse survivors. She explained her interest in the documentary by applauding how well it conveyed the insidious nature of child sexual abuse that she endeavored to illustrate on her syndicated program.

"This is a moment in time that allows us to see this societal corruption. It's like a scourge on humanity," she said, adding, "If it gets you, our audience, to see how it happens, then some good would have come of it."

The Jackson family has condemned the documentary, denying the allegations and his estate has filed a lawsuit against HBO.

Winfrey guided Safechuck and Robson through a discussion in which they echoed what they said in the film, asking whether as children they understood the nature of the relationship and the way that Jackson was allegedly "grooming" them.

"I had no understanding that what Michael did to me sexually was abuse," Robson said. "I had no concept of it being that."

Winfrey also explored why the two men continued to associate with Jackson in the wake of what they say transpired. Winfrey pointed out that people need to recognize what she described as the "god"-like position that Jackson occupied until his death in 2009.

"The grooming had started long before we ever met," Robson noted, citing Jackson's stardom and his image.

Both men attributed their decision to speak out in part to having children themselves, which forced them to come to grips with a secret that Robson said he had intended to take "to my grave."

"I'll be working on this for the rest of my life," Safechuck said, adding later, "This moment will end. And I still have a lot of work to do."

The presentation incorporated members of the audience, including former "ER" star Anthony Edwards, who published an essay in 2017 saying that he had been sexually victimized as a youth.

Winfrey read the statement issued by Jackson's family disputing the film's allegations. Reed didn't reach out to Jackson's family but drew extensively in the documentary from interviews with the singer, including one conducted by Martin Bashir for ABC News in 2003.

Reed reiterated that he didn't see any journalistic value in having family members denying the claims when only the then-boys were with him when "the bedroom door closed." He added that the estate has "a gigantic vested interest, a financial interest, in smearing these two young men, and in discrediting them."

On Feb. 21, the Jackson estate sued HBO, contending that by airing the documentary the network had breached a non-disparagement clause in a 1992 contract. HBO subsequently announced that it would air the Winfrey-hosted special to follow "Leaving Neverland" and further address issues raised by the film. The program ran concurrently on Winfrey's OWN cable network.

HBO responded to the lawsuit by saying that the network would air the documentary and "allow everyone the opportunity to assess the film and the claims in it for themselves." "Leaving Neverland" premiered at the Sundance Film Festival in January, garnering strong critical reaction. (Like CNN, HBO is a unit of WarnerMedia.)

Both Robson and Safechuck had defended Jackson in the past, with the former testifying on his behalf at Jackson's 2005 child-molestation trial, which ended in his acquittal. In the film, they talk at length about the way Jackson seduced them and later pressured them not to speak of the sexual abuse, which, they claim, went on for years.

At the taping, Winfrey, who conducted a widely-watched live interview with Jackson at Neverland in 1993, before the allegations of sexual abuse were made public, acknowledged that her involvement in Monday's special would open her up to criticism from Jackson's die-hard fans, who have vigorously pushed back against accusations that they have long characterized as money grabs and attempts to cash in on the King of Pop's legacy.

Robson and Safechuck filed separate civil lawsuits against Jackson's estate in 2013 and 2014, respectively. They were dismissed in 2017 on technical grounds, according to their attorney, but remain under appeal.

Attorneys for Jackson's estate have called the documentary "a one-sided marathon of unvetted propaganda to shamelessly exploit an innocent man no longer here to defend himself."

Opening the program, Winfrey noted that the studio audience had just completed watching "Leaving Neverland," which she described as "an intense and emotional experience for many people here." She hugged both men when the conversation concluded.