AUM is a real, complex, large system. Such systems usually have parts or subsets that are both increasing and decreasing entropy at any one time. The evolution of the system depends upon whether or not the average entropy of the system is increasing or decreasing. In PMR we have things decaying while other things are growing. The Second Law of Thermo says the average entropy of the PMR universe must increase with time.
I am not sure where you are in the trilogy but at several points in Book 2 there is a discussion of the "consciousness cycle," which should answer these questions. In general , AUM's successful evolution does not necessitate that humans succeed. Humans are just a tiny subset of AUM -- the larger systems success is not dependent on one tiny subset. However, our point and purpose is to add to the systems success, and the system is set up to encourage us to succeed in that purpose, but we have to succeed or fail by the exercise of our own free will. We have an opportunity to succeed, we are nudged and prodded to succeed, but it is up to us.
You are correct. There is no free lunch. If we do not earn our success by individually and collectively growing up, increasing our quality, pulling ourselves up by our bootstraps, then we fail. We must earn our way, every tiny increment of our progress -- this is not a game of monopoly where you get $200 just for passing "Go". Only wishful thinkers, those hoping for a free hand-out, and those who do not understand the nature of the consciousness system believe otherwise.
This vibration thing is just a metaphor. AUM is not vibrating, neither are our energy bodies. Consciousness is organized information, it doesn't vibrate. Habitual PMR associations makes frequency a sometimes useful but often misleading metaphor.
Any real system or subsystem must evolve, maintain stasis, or die. Stasis is not a stable state for interacting self-modifying sentient systems like consciousness. Evolve and grow or wither and die are the practical options. This ultimatum is generally true for all levels of the consciousness-evolution fractal reality. True for AUM, for PMR, for humans, for our souls, for viruses and dogs, and for political, technical, economic, and social systems as well. We are all part of one large system and thus all are in the same system boat. Fortunately, it is a big boat.