The only basis I can see for reopening the investigation into Tawana Brawley's case from 1987, as requested by her mother and stepfather, is the advance in forensics analysis in the last 20 years which is the identical basis used by convicted rapists to have their cases reviewed.
Even if some of the investigation techniques used back then to support the idea that the case was a hoax have been shown to be unreliable, only evidence which undeniably links a specific suspect to the case would have any chance of seeing anyone charged related to those allegations.
However, one or more DNA matches would be significant since the original defense was that the allegations were a total fabrication. So if there is any DNA matching the suspects, the "it was consensual" defense would be non-credible.
If old convictions should be reviewed because unprocessed DNA evidence may exist that could confirm or contradict what some believe to be an incorrect outcome, then those who reported being a crime victim should have those same rights.
If the outcome of the case was right the first time then a review of the evidence won't uncover anything that will hurt the original suspects. The review might be quick if all of the forensic evidence collected in 1987 is gone.
The reaction of those who consider this case a hoax will be interesting especially when contrasted to their position on exoneration efforts.
For anyone who doesn't acknowledge that investigators can unfairly come to the judgement that a real rape victim is a liar, please read Cry Rape: The True Story of One Woman's Harrowing Quest for Justice by Bill Lueders.