The fault was really CNN’s. CNN put out a report with a big chyron underneath saying Carson ‘taking break’ from campaign and then saying he intended to skip NH and South Carolina. This kind of language is common when one is suspending a campaign. The Cruz team was reacting to that.
It also didn’t occur until around 8 pm. At that point people were already caucusing and voting. It would seem unlikely that anyone would change their vote over a report at that point, especially if they were hearing it from an opponent.