Here's the answer from the Associated Press, on the ABC News website, which was found via a (likely accidental) link on ESPN.com:
The woman's lawsuit says she didn't file a criminal complaint because she feared Harrah's would side with Roethlisberger and she would be fired. The suit doesn't say whether the woman is still working for Harrah's.
So there's that, for the great many people out there who like to play amateur lawyer and/or presume to know exactly what went on in that room that night. The question does have an answer. You may choose to not find it plausible or believable, but there is an answer on record.
In other Roethlisberger news, Roger Goodell acknowledged yesterday that the lawsuit is "something that [the NFL] obviously will look into". I think that leaves ESPN and Steelers.com as the only news outlets on the planet not reporting the story.