If that is correct, then the issue may simply be whether the legislature is empowered to have a rigged election decide the issue. Are they obligated to set aside an imperfect election? When has there ever been a perfect election?
I am having trouble seeing the Supreme Court dictating anything other than pointing out that the legislature has the power to reject the election results or accept the results as they see fit. Would that be enough to help us? I am not so sure.
Your crossbow does not hit far from the mark. There is definitely a separation of power issue. Marbury v Madison avoided the problem by declaring a law unconstitutional. Assuming that SCOTUS decides that the U.S. Constitution or Federal Law was violate and therefor votes cannot be counted based on the violation. Since we do not know exactly which votes are illegal, the only choice is to decide that none of the votes can be counted. So far so good. What if the State decides to certify? SCOTUS could say the certification is a nullity. What if Congress decides to certify the election for each of the defendant swing states.
The effect would be that Biden is not a legitimate president and you can bet that Trump will not leave the whitehouse under these circumstances. Furthermore, if Democrats are in control they are going to pack the court. I’m pretty sure the Justices do not want that.