Alternatively, if the state calls the election decertified, then Gov. Ducey could simply declare the vote so confused that he must appoint a senator for that seat until a special election can be called.
Spaceman Kelly was seated in the U.S. Senate and given the oath of office. Even if AZ decertified him as the winner, it would be the U.S. Senate that would need to exclude him from the Senate via majority vote (the U.S. Constitution empowers each house of Congress to be the judge of the elections of its members) and create a vacancy that Gov. Ducey could fill until a special election is held, or perhaps even seat McSally as the rightful winner of the 2020 special election. So it *could* happen, but it wouldn’t be something that the State of Arizona could do unilaterally.