I am sorry to hear about your daughter. You are correct. This is a he said/she said type of case, so the best recourse you have to protect your daughter's rights is to make sure she has a lawyer to help her fight this case.
I know that you think that the system has not afforded your daughter an opportunity to be heard. I'm sure you think that's unfair. But, in fact, that is only the way our system works.
To make an arrest and to file criminal
charges, the state only has to have something called probable cause
. Probable cause is just a reasonable belief that a crime may have been committed and that a particular person may have committed it. The word of a believable-sounding complainant, even if she and her mother are lying or exaggerating, is in most cases enough to yield probable cause. They do not have to go any further to investigate once they feel they have probable cause, and your daughter's lawyer will be very grateful that they did not call your daughter in and dupe her into making a statement but instead honored her 5th amendment rights. Your daughter gets her day in court if she wants one, she has an fundamental right to a trial
You are probably thinking that the police need hardly any evidence to arrest somebody, and that anybody can get anyone else arrested if they have a mind to do it. Unfortunately, you'd be right, and it's amazing that it doesn't happen more often than it does. But what you have to realize is that if the state needs next to no evidence to make an arrest, it needs an incredible amount of evidence to get the conviction. That's because the prosecutor must prove each and every element of each and every charge beyond a reasonable doubt to get a conviction. There is no heavier burden than this in our law or, for that matter, in any other nation's.
Note that I said that the prosecutor must prove his case beyond a reasonable doubt. Under our legal system, a defendant does not have to prove her innocence. She is presumed innocent unless/until she's proved to be guilty beyond a reasonable doubt. So she does not have to prove a thing. The state is the one who has to prove anything, and if the woman and her daughter are exaggerating or lying, a lawyer should be able to make that information apparent to the jury through cross examination of the witnesses at trial. Further, if she chooses, she can testify at her trial and put her story out there. If it creates reasonable doubt in the minds of the jury, or the judge if it's a judge trial, then she cannot be convicted of these charges.
So let your daughter talk this over with a lawyer, who will help her determine how to proceed. She will have to choose -- as all defendants in criminal cases do -- between accepting a plea bargain or fighting the case. Her lawyer can look at the court papers, confer with the prosecutor as to the state's evidence and see discovery material and tell her the up and down sides of the case. It is likely, incidentally, that should she wish to dispose of this, she could come out of this without a criminal record
, but her lawyer can discuss that far more knowledgeably after conferring with the prosecutor.
Hope this provides you with some general guidance.