Irrefutable proof would mean that it actually was litigated and investigated. So far, not a single court case proceeded, mainly over standing which is a judge's way out when they don't want to get involved in something. The AZ audit is the first actual investigation and audit. Everything else has been a recount, which doesn't go into any forensics.
But... in the process of staying out of the election results, the Federal courts including SCOTUS have reaffirmed state legislatures are empowered to set the times, places and manner of congressional elections. That's why Nancy and Chucky are so hell-bent on getting HR-1 pushed thru -- they want to take away power that the Constitution already assigned to the States, but I don't think it will work, nor will it appear to pass the Senate.
As for all the new laws... wait and see how those challenges proceed. At the surface, the most recent laws passed seem to be staying within the bounds of what's already become settled case law. Voter ID is here to stay thanks to the Courts. Determining the days and hours of early voting and parameters for mail-in/absentee ballots was always clearly with the State Legislatures to define.