It isn't a story. Just some folks trying to make it into one.
Yes, and most of them will not endorse unless asked specifically by the candidate running to do so.
We are Texans, you and I, and I cannot speak for you, but I can say that I have met no one would will not cast a vote for Senator Cruz in 2018.
Everyone that I have spoken to has told me they will.
Anecdotal evidence, to be sure, but we see Cruz now fighting to not lose control of the internet, and other things he has stood up to, and he is viewed in a more favorable light than Cornyn is.
IMO, Perry would not be able to do so, and to try would tarnish his own brand, and he is wise enough to know this.