If she truly wants this she should testify and present her information. If she chooses not to testify the Senate should proceed to a vote without her information.
She will testify to the FBI if they demand it. Anyone actually wanting the truth should be doing whatever they can to get the information from here, if only the president could make an agency do some digging to find out the truth, gee that would be sweet.
That's not how the criminal justice system works. You file a criminal report (ideally not 30 years late), and you provide the appropriate law enforcement agency with as much information and evidence as you can provide. The standard protocol for filing a criminal report is making an official statement. If there is no report, no statement, no evidence, there is
no investigation. You don't get to demand the FBI go dig through some ones life just based on statements alone. That is their discretion, and right now, because of the lack of any substantial evidence or an official report they would be doing little more than interfering with the confirmation process.
Of course interference is what some people are seeking. Also filing a false report is a crime. So naturally anyone making false accusations would avoid making an official report to authorities. Considering the accusation itself would achieve the goals intended by making a false accusation, it matters little and she will never be held accountable. Women who are proven to make false accusations of sexual assault or rape rarely are.