I had an old Horton decocking bolt that I used for 5 years. It was solid fiberglass and indestructible. I shot it into some soft dirt and can't find it any more. Gotta see if I can scrounge up another. All other decocking gadgets did not last. For now am shooting a field point into a bag target.
Don't worry about the Omni nock. Just use the moon nock and load it properly. I had a couple of TP's with Omni nock requirements and used moons many times. Omni's are good because you can't load them incorrectly.