Texan is correct. The fact is, the pitcher gets the ball on a "SAFETY SQUEEZE", obviously the runner at 3rd is going to be down the line a bit (not like a suicide) but he will be down the line. What the pitcher chose to do is look over at the runner at 3rd...right at this point he is keeping the runner from scoring (he did accomplish something). So at that stage the scorekeeper makes the judgement that there was NO ERROR (it's up to the scorekeeper to determine if an ERROR was made). So, since NO ERROR (no bobble, no errant throw, no nothing), the pitcher had a choice to make , 1) keep the runner at 3rd by simply looking that way with body language, 2) Make a throw to 3rd base and try to get the run-down going, 3) Get the out at 1st. He chose to keep the runner at 3rd. Good decision, no run scored ant you live to pitch to another batter.
FIELDER's CHOICE ALL THE WAY with NO HIT, NO SAC, NO ERROR scored. It's simply an FC clear and simple. Don't try to make it too complicated. Don't give a hit where a hit is not due. Always lean toward giving the defense the benefit of the doubt because that's the way it's going to be once they reach high school and beyond! Do them a favor, teach them early.