The problem is that you can’t claim something to be out of necessity or expediency if, in practice, you frame it as a great and tremendous thing you fully support. “Vote for Moore so we can replace him with a better Republican later” is not the same thing as “this is a wonderful great guy America needs and you should vote for him plus also that lady lied.”
But that is where Trump is putting the GOP. It’s an affirmative support. A declaration of Moore as suitable and one of us. It’s not a candidacy endorsement, in other words. It’s a Moore endorsement. There will be no expulsion should he win. There can’t be. He’s Trump’s chosen.