No State has yet declared a 'Certified' election result. News media may deem Bidon to have won but until each state announces Certified results and that state's House Representatives and Senators sign off, there is not yet an official winner.
At this point, Republicans cannot claim a corrupt election as the states in question have been unwilling to cooperate. It currently appears those states will need to be forced to provide details and explanations, to complete an audit or recount the results which is why Trump and other Republican Senators are launching lawsuits.
There are currently too many suspicious practices that occurred and many post office and ballot processing employees have been coming forward to swear affidavits on improper practices they witnessed or were forced to participate in by those in positions above them. Election Scrutineers appointed by the Republican party have also been providing testimony on how they were prevented from witnessing how ballots were processed.
Ballot processing is to be open to being observed by anyone and each party appoints Scrutineers to closely witness the process to ensure fairness. Scrutineers appointed by the Repub's were often denied access or were forced to stay up to 100' away from the process. Windows were often covered over in certain areas and election results for Biden often drastically increased after processing was shut down for the night and after Scrutineers were sent home.
Since the US claims to set the example to the world in allowing 'the people' to choose their President and Government in a fair and balanced manner, every US citizen should be supportive that unusual, suspicious and improper election practices are investigated and are corrected.
While Democrats wined for 4-years that the only reason Trump won in 2016 was due to Russian influence so Democrats should be all the more supportive to have this election investigated and reviewed to ensure similar accusations are not made against the person they chose to be President.
The Constitution authorizes each state's Legislature as fully responsible for how each election is to be administered for that state. Neither the state's Governer nor Supreme Court has authority to override that state's Legislature.
The Constitution specifies an 'election day' so unless each state's Legislature decides to extend how long ballots may continue to qualify past the election day, each state's Supreme Court cannot legally change how long ballots may continue to be accepted, regardless of the reason.
Court's and Judges do not create or change laws but are to act as referees in ensuring the laws created/modified by those that are elected are correctly and fairly carried out.
The Consitution builds in safeguards in how matters such as this are to be resolved. While there are various steps to be first taken such as those currently occurring, the ultimate responsibility for naming the President chosen by each state is in the hands of the newly appointed House Representatives and Senators for each state.