According to Jim: Season 5, Episode 4
5 - 4: Charity Begins at Hef's
When Cheryl wins two tickets to visit Hugh Hefner at the Playboy Mansion in a charity-raising contest that Jim secretly entered her in, she decides to take Dana instead of him.
When Cheryl wins two tickets to visit Hugh Hefner at the Playboy Mansion in a charity-raising contest that Jim secretly entered her in, she decides to take Dana instead of him.