There is definitely end rhyme in this
The correct answer is Jerry.
Since Kevin and Mark eat carpool with the manager, that means that neither of them is the manager.
That leaves two options: Jerry and Tom. But later on, we are told that Tom watches TV with the manager.
Therefore, the only possible answer is Jerry.
This scene occurs when Balfour is on the small islet. Balfour gives into despair when he tires to cross the river but cannot -- it is too deep. He finds that his "yard" (a piece of wood he was saving to float on) has been carried away. Believing he has no way to escape the islet, he gives into despair and weeps.