Cruz is being discussed because his refusal to endorse Trump equates to getting on the same train Ryan is on and finding "sensible" ways to help others decide that Trump isn't worth backing and that will result in some thinking they can thwart the will of the People by shenanigans at the Convention. If that happens, Cruz likely has some small hope that he may be the beneficiary of such manipulation.
Jumping on board with those who would weaken Trump against Hilary now is akin to treason in the Party - anything less than an actual and timely endorsement, weakens Trump - the rest is sedition at the candidate level..
Jumping on board with evil is wrong on all levels. At least I recognize where evil is, unlike others who fully abandon principles and convictions because....>Republican.