They can post it somewhere with standards of evidence if they want to be taken seriously. Why waste time looking into it on the off chance it has more veracity than everything around it?
A glaringly obvious logic fail is “any apparent fraudulent behaviour must be on behalf of the winner” - er, no - it would be much more likely for the intended benefit of the less ethically sound candidate.
(Which one that would be in this case is an exercise left for the reader)