Yes, he can proceed on that basis, but ultimately it is not a Constitutional ruling.
But then it has to go to court. That takes time and time is of the essence here, as the document cards are already being prepared. And as I have said elsewhere here, once the illegals have jobs, apartments, and bank accounts, it really would be inhuman to deport them. Now is the time to stop this, not when the legal groups get around to it and it wends its slow way through the court system.
It occurred to me that it is no anomaly that this was rushed through—while we still have a lame-duck Dem Senate.