I think I get it...
If Trump fails to get a majority of delegates before the convention... I don’t think that it will matter what the repercussions are. Neither Cruz or Trump will get the nomination. A vote for Cruz or Kasich is a vote to leave the establishment firmly in control. This is the narrative that Trump needs to pivot to.
I think that Cruz may play ball when his mathematical possibility of getting to a majority of delegates before the convention disappears completely. His conservative principles, his ability to argue, and his mind could do the most good in the Supreme Court.