Freezing shoes to kill the smell does work.
You can place your smelly shoes in a sealed bag and then place them in the freezer overnight and it will kill the bacteria in the shoes that is causing the smell.
You can also add some baking soda to the shoes to keep the odors from coming back.
The freezing cold temperatures of the freezer kills the bacteria causing the odor in your shoes so the smell goes away.
I've done it myself several times and the freezer really does kill the odor in the shoes.