You had one part right on target...”The office of the Presidency is over”.
If Arizona law is “unenforceable” it will be because he makes it so. Let it work and then say it is “unenforceable”. But, if he lets it work and it is successful, he’ll look even dumber. So that means he will fight it all the way.
I don’t think there’s any way he could look “dumber”, but he does have ways of surprising us