Where does the energy go? Into the crushed foam. Energy is energy, and having something absorb it, other than your head, is the key. The foam is hard to crush, therefore it absorbs more energy. Soft padding is easy to crush, therefore it absorbs much less energy. In an impact all the soft padding is rapidly compressed, absorbing almost no energy, and then your head impact the hard shell, and virtually all the energy is transfered directly to your head. This point isn't really open for debate. It's fact, proven by years of testing and product development across various industries.
Your problem is you're vastly under estimating the how much energy the foam can absorb, and vastly over estimating how much energy your soft padding can absorb.
B the way, your example is useless, as the weights and energies are so far off.