A source told LifeandStylemag.com: "They wanted to bring back a real ex."
A friend of Denise's said it was hard for her to say no, but she didn't want to upset her former husband – who reportedly settled a $100 million payout with the show's makers over his being sacked earlier this week.
Denise knows where her bread is buttered
The friend said: "She really wants to get back into TV. But Charlie would've gone crazy, and Denise knows where her bread is buttered."
In the show viewers saw Charlie's on-screen brother Alan Harper - played by Jon Cryer – drop his character's ashes all over the floor.
It was also revealed the actor's alter ego had died when being hit by a Paris subway train, shortly after admitting to his new wife, Rose, he cheated on her.
Rose told the congregation at his funeral: "I just want you to know that Charlie didn't suffer. His body just exploded like a balloon full of meat."
A new lead character was also introduced to the show, played by Ashton Kutcher.