Here's the link again. It says that the case may be close to collapse, not just because of questions over her reliability (specifically it seems, because of earlier rape allegation she had made:
"The officials believe the woman lied on her application for asylum in the US, particularly over an allegation that she had been raped while at home in Guinea, in West Africa. "She actually recounted the entire story to prosecutors and later said it was false," one law enforcement official told the Associated Press news agency".
But also the article says:
"But prosecutors have not necessarily reached a new conclusion over the allegations against Mr Strauss-Kahn and have not decided whether to downgrade the charges, the official said".