Seems like in 'big cases' (such as the Epstein one) when there's a ton of victims, the plaintiff's attorney and/or DA selects a handful of victims or sometimes even just one - the one(s) with the most solid evidence, the most credible, corroborated cases (with multiple witnesses willing to testify to the same thing) - to do the prosecution with.

I was such a witness/victim of a violent crime who was chosen as "the case" to try out of a handful of similar cases against the same perpetrators. The way my police detective explained it to me, what typically happens is if a perp is prosecuted for the same crime a dozen times, 100 times, 1,000 times, however many times, even if the perp is found guilty for each instance, the sentence for each crime usually "runs concurrently."

Translation - if some scumbag rapes 10 women and gets a 10-year sentence for each rape, the perp often wouldn't be sentenced to 100 years - they'd just get 10 years. Therefore, the prosecutor tries to find the absolute strongest case(s) and witnesses against that perp in order to at least get any prosecution at all.