Nothing currently suggest there has been any breakage and sucked into the eninge of the plastic flaps. If any do break, it will be consumed by the engine which has the potential, but no assurance, that damage will be done. Since the flaps are not something easily burnt by cylinder firing, having the fragment anywhere in the engine is not a good situation. It can get wedged in a number of palces like a valve, which will do more damage to the engine. More likely, at this point, carbon has bound up one or more of the plastic flaps and it is that which is keeping movement of the flap system.You have to remove the manifold again to see what the situation is with them. I suspect they probably broke off and were sucked into the engine. BTW, they aren't going to get involved with the valve train unless you have some unknown passages in your engine.