Wouldn’t flash cooling inside a freezer ice cube box be as effective as an ice bath?
I was a mechanical engineer.
The heat transfer will be much quicker in the ice bath because you will have full surface contact between the meat and the water, even into all the nooks, cracks and crevices of the meat. This is not possible just putting it in tghe freezer. Water is a great conductor of heat. Air is an insulator. You will have parts of the meat surface insulated by air.

There are other, greater, problems with your suggestion in lieu of the ice bath. When is the last time the freezer box was sanitized? Probably never?
Where does all the melted ice water go? Into a puddle at a low spot to refreeze?
You are bringing odors into the freezer box.
The meat is picking up odors from the freezer box even though you might not be able to smell them or are just aclimatized to them.