I’ve read something similar, but I don’t recall the guy actually being fired. No doubt he was merely following orders from the Sales Department.
At one point in preparing the first pilot, Nimoy began to have doubts about playing Spock and tried to quit. As a last resort, Roddenberry promised to personally write a script in which Spock got an earjob if Nimoy felt the same way after the thirteenth episode.
At another, Bob Justman put Nimoy on by saying they wanted to send him to a plastic surgeon so he didn’t have to bother with the ears every day, and then they’d pay to have them put back to normal when the series ended. He almost had Nimoy believing it.