Your reasoning is faulty. Kasich does nothing but ensure a brokered convention. He prevents useful votes. Almost 100,000 people in. Ohio choose to vote for Kasich who can’t win. If he were gone Cruz and Trump would both do better.
Of course, it's just a theory. But why else would Kasich be campaigning in Utah, if not to attempt to keep Cruz under the WTA threshhold of 50%?
I still think Cruz will win Utah. Fealty to a church leader (Romney) will carry the day.
The question is whether he can be held to less than 50%.
Trump will win Arizona in a romp. If he can eat into Utah's delegation, that's a big win.