In truth, dynamic emptiness has absolutely nothing to do with quantum froth, which could be described using any objects and still make sense. This concept of some unseen physical manifestation of the model arises because of the terms a theoretician chose to identify elements of his mathematical model. They're essentially undefined terms, given meaning by their context in the larger physical system.
A lot of people get lost in the undefined terms, thinking that because we use a familiar word for the term, that the item in the model which the term identifies somehow actually exists. Actually there's no proof that the quantum froth exists as physical object, any more than that light is somehow both a wave and a particle. Rather, wave/particle "duality" is a consequence of different mathematical models which happen to generate results which are consistent with observation.
The "duality" doesn't actually exist, and the way light behaves is so incredibly nuanced that people dedicate their lives to modeling and testing it. Waveness and Particleness are models which produce mathematics consistent with the natural world.
In the cases where more than one mathematical model fits the same set of observations, scientific controversies arise. A Physical theory is accepted when the mathematical model produces results which are consistent with observation, and sufficient experimental work has been done to rule out other mathematical models with overlapping explanatory power.
My thermodynamics professor opened all of his classes by saying "Everything I am about to tell you is a carefully constructed series of lies."