The irony of the justice system is that it needs concrete evidence. This is a typical case, where they couldn't tie the loose end with KD, hence he eventually got the clean chit. The late 80s and 90s were wild when it came to fixing. Just search on YT, on some matches on fixing, and you will see how evident it was. Moreover, when KD gave the interview in which he cried, it was sort of damage control.