I'd argue that in such a case preventing such a person from seeking justice would be wrong, since they were really victims and diserve redress.

If the system isn't actually going to give them redress then what benefit is there in consuming the resources of the complainant and the court only to end up with the same result? The problem you have to solve in those cases is how to make it so someone with a meritorious claim would have a high probability of winning.