That's what she meant. The Old Man is like the judges, but more powerful. They don't seem to be able to control it, and it eats people more literally. If it catches you, it will pull you into the rock, where you'll be slowly consumed in a state of not-quite-death over a long period of time.
Don't let it catch you.
In any case, King is the judge who seems to have some measure of control over the other judges. He is the one who has, presumably, organized this game system. We've found evidence that other groups of people like us have gone through something similar to what we have, and in the end were consumed by the earth. For various reasons, we suspect that at a certain point, King writes his players off as a loss and instead gathers a new group to begin the feeding cycle over again. That point has passed already.