But I'm not certain what you believe justice would consist of in this case. As you wrote, no one knows what happened in that room. Given that Virginia was unwell, possibly from a previous abortion, even consensual sex with someone Arbuckle's size might have been dangerous for her.
And Arbuckle's career was destroyed, despite his acquittal.
Given Fatty's earning power, the studios might have tried to cover the whole thing up, as they would later do in the murder of William Desmond Taylor. Instead, Fatty underwent three trials, based on the assumption that he had, indeed, sexually assulted Rappe & caused her death. She was believed.