In an interview with ET's Kevin Frazier about Meghan and Harry's bombshell sit-down with Oprah Winfrey, Nicholl said Queen Elizabeth II and the royal family are taking the couple's allegations -- particularly about racism -- very seriously.
"The queen's mantra has always been, 'Never complain, never explain.' I think the Palace was hoping and certainly newspapers were being briefed over the weekend that this would just be a storm that blew over given time,'" Nicholl shared. "I think we've all realized on both sides of the pond that this storm is not going to go away anytime soon."
"The can of worms has been opened, some very serious things have been said and I think the Palace really have no choice but to issue some sort of a comment," she added.
"It's opened up a Pandora's Box and there is something of a witch hunt to find out which royal it is," Nicholl said. "The suggestion is that if it's Charles, if it's William -- that's a very big if, no one knows, it's pure speculation -- then that has real repercussions for the monarchy. Charles is going to be the next king. After that, William."
Nicholl speculates that Harry realizes the "seriousness" of the claim, no matter who was involved. During his interview, Harry spoke lovingly about the queen and his brother William, but said that his father had been strained -- to the point where Charles was not taking his calls for a period of time.
"To be honest, I don't think it really matters which member of the royal family said it," Nicholl said. "It's the fact that a member of the royal family expressed those views. Who is almost irrelevant, the concerning thing is that someone felt that way."
"These claims have come on Commonwealth Day, a day that is incredibly important to the queen. She's very proud that she presides over so many multi-racial realms and countries," she noted. "And there is a feeling of shock over here at these allegations, a feeling of disbelief and certainly among some commentators and some parts of the public who are clearly very divided on social media, a huge amount of offense that the queen, the institution, the royal family is being accused of racism."
Regardless of the questions over which member of the royal family could have expressed concerns over Archie's skin tone, Nicholl said Harry's reveal that Charles had at one point stopped taking his calls has hurt his father's reputation.
"I think it is very damaging for Charles' reputation to be seen as a cool and aloof father. Don’t forget he had that reputation around the time of Diana's death. People said he wasn’t there enough for his sons," Nicholl shared. "Well now here is Harry saying himself that later on... his father wasn’t there for him. And I think at a time when Charles' reputation is enjoying more popularity than arguably it has ever done -- he's been a real hit during the pandemic. People have really warmed to Charles -- This is pretty damaging."
In his interview on Sunday, Harry told Winfrey that he had hope he'd repair their relationship.
"There's a lot to work through there, you know?" he acknowledged. "I feel really let down, because he's been through something similar. He knows what pain feels like, and this is-- and Archie's his grandson. But, at the same time, you know, I-- of course I will always love him, but there's a lot of hurt that's happened. And-- and I will continue to make it one of my priorities to try and heal that relationship."