If for whatever reason the victim told an elder first, then I agree that that elder should report it (especially if it was mandatory law to do so, which is why all states should all have such laws) but if an elder was not told first, then whoever was/is should be the one/s to do so.
If the parents tell the Elders and no one tells the police, all of them, the parents and the elders should face legal concequences for not reporting.