The problem is not that a ring wasn't followed properly. The problem looks to be(I can't be sure because as I can't see the other edge of the limb) is that you didn't compensate for the knot, in the width of the bow, at that spot. Pin knots have significantly less strength in tension and compression than clear wood, so there is effectively not enough tension strength at that spot. If a pin knot is 1/8", then make a swell in the width 1/8", at the same spot.
Some people are lucky, or overbuild the bow and get away with it. Will it break anytime soon? Maybe. Its just as likely to break catastrophically without a further apparent degrade, as it is to slowly show an increase in the width of the crack, or go no further and shoot safely.
If it were mine I'd back it with rawhide.