"I just can’t be fake," the New York Post quoted her as saying. "It’s discrimination, and it was badly handled."
Representatives for the show said during the Television Critics Association summer press tour last month that Jack Osbourne, 26, had been in talks with the military-themed reality competition.
Producer David Hurwitz said the "rigors of the show were too intense for him."
Sharon Osbourne caught NBC executives off-guard when she tweeted to fellow "AGT" judge Howard Stern on July 24, the day of NBC's TCA presentation, "My darling @HowardStern, money is not the reason I'm not returning to @nbcagt, it's because..."
She left it at that.
NBC did not immediately respond to a request for comment Monday. NBC entertainment president Bob Greenblatt told TheWrap after Osbourne's tweet that he hoped she would stay with "AGT."
The Post said both Osbournes acknowledged that Jack Osbourne's contract was never signed. But they said he was moving forward with the network based on a good-faith, verbal commitment. Sharon Osbourne said she had a similar agreement with NBC before formally joining "AGT."
She said that under her contract, NBC can't force her to remain with the show.
"They can't make me do something I don't want to do," she said. "All they can do is stop me from being a judge on another network for five years."
Jack, who completed a 30-mile, 16-hour endurance race in January, was first approached by "Stars Earn Stripes" in April, the Post said. The show sent an email in May confirming his participation, and in June he went public about having MS.
He was dropped two days later, the Osbournes said. Jack Osbourne went on his mother's show "The Talk" at the time to contend that he was fired because of MS.
