If their was one person in the White House with any brains, they would cancel that EO and write one directing all the vetting agencies to review their procedures to see if they can improve their process in any way. It may not really be possible (since they are working perfectly now) but I assume most of them could come up with something that would LOOK like an improvement. Like make a waiting period 90 days instead of 60.
Then Trump could write another EO directing them to do some of those and declare victory.
But of course we now have a head-butting contest that won't stop until somebody passes out. It will go the the Supreme Court and lose, badly. I would not be surprised at a 8:0 decision. Maybe this is all it takes to make Trump resign in a tantrum?