The reason you’re seeing this Cruz-realization revelation is because the GOPe still hates Trump because they won’t be able to control him -ever, not like they did with W. or HW for that matter.
But the dirty little secret is though, that they HATE Cruz, too! What they’re doing is fomenting unrest and disease between the two camps while simultaneously keeping Rubio and Kasich in the mix (when a sane candidate would have dropped out already) JUST to keep Trump and/or Cruz from getting that magic number of delegates.
The very last thing they want is to have either the Trump camp coalesce around Cruz or vice versa. So with Trump leading they throw a meatless bone of hope to the Cruz camp in order to keep them in place - all spoiling each others’ chances. Rubio is there to deny Cruz, and Kasich is there to Deny Trump Ohio, maybe Illinois.
GOPe wants a first vote failure in the nomination convention so they can trot out whatever relic they have waiting in the wings.
And that relic may very well be Mittens. He did file papers with the FEC in January. That's on record.