I do not regard the Cuban Missile Crisis as a success for containment because it did not really prevent the spread of communism.
You can argue that it was a success because it prevented the Soviet Union from becoming militarily stronger. Having missiles in Cuba would have (temporarily) been an important strategic move that would have strengthened the Soviets' position in the world.
However, the crisis did not actually prevent the spread of communism. After the crisis was over, Cuba was still communist even though it had not been communist a few years before. In fact, after the crisis, the US pledged not to invade Cuba, thus allowing communism to remain in Cuba after having spread there.
The Cuban Missile Crisis did not prevent the spread of communism, therefore I do not see it as a success for the strategy of containment.