I think he should try it anyway. If he must, go to court and the election commission to show reasonable cause. See if the legislators show up to avoid court. See if they take any illegal donations to defend their seats.
The Rats would do it in a heart beat. Time to play it their way.
The governor DOES have the authority to call for an election to fill a vacancy, he DOES NOT have the right to declare a seat vacant...however, a simple majority of the legislature does.
If the Repubs who control the WI legislature have the juevos...they’ll do it.