The 47-year-old star was controversially let go from the judging panel of the NBC talent competition alongside Julianne Hough after they spent just one season working on the series.
And as someone who was a judge on the talent contest for six seasons until her departure in 2012, Sharon, 67, shared her own experience, explaining she only left ''because of NBC'' and not because of the atmosphere on set, as she insisted ''the crew and everybody'' were ''amazing to her''.
On Monday's (02.12.19) episode of 'The Talk', she said: ''It's hard.
''Everybody's experience on a show is different, and I was at that show for six years. I didn't get let go.
''I left. And that's the truth. I left because NBC, not because of the show.
''I had my own problems with the network.
''I don't know about any of her concerns about the show.''
Sharon didn't want to comment on Gabrielle's concerns over the racially insensitive acts on set.
She added: ''Obviously, there wasn't anybody of colour on the panel when I was there.
''So, I honestly can't say.
''But when I was there it was, you know, a great show to work on.
''The crew and everybody was amazing to me, everybody, except the network.''
The TV network and the two production companies behind the show, Fremantle and Syco, issued a statement on Sunday (01.12.19) in which they claimed they were ''working with'' the actress to understand ''concerns'' following reports of a toxic environment on set, as well as her concerns over the insensitive acts and personal remarks about her appearance.
However, she was unimpressed by their response.
Gabrielle retweeted a post from writer Joelle Monique which read: ''A solid apology comes in three parts.
''1. Sincerely admit wrong doing directly to the offended party.
''2. Be twice as loud correcting your mistake as you were making the mistake.
''3. Lay out steps to correct your behavior in the future.
''Anything less is covering your own ass.''
Alongside her retweet, Gabrielle wrote: ''This! This! AND THIIISSSSSSS!!!!!!(sic)''.
NBC had insisted they are ''working with'' the former talent show judge to understand her ''concerns'' about the show.
They said in a statement: ''We remain committed to ensuring a respectful workplace for all employees and take very seriously any questions about workplace culture.
''We are working with Ms. Union through her representatives to hear more about her concerns, following which we will take whatever next steps may be appropriate.''
Meanwhile, Julianne has denied experiencing any problems on set.
The 31-year-old dancer said in a statement last week: ''I had a wonderful time on 'America's Got Talent.' I loved working with the cast, crew and producers.
''I am happy to continue my working relationship with NBC... I'm looking forward to what the future holds.''
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