Let's say I've got a cooked fish sitting in ice, scales & eyeballs included, how do I get that to a state where I could serve it? Is there a recipe where already-cooked frozen fish is an ingredient?

You serve the whole fish, it's not that uncommon in some cuisines. I can't imagine why you'd want raw fish skin and cooked meat though (there has to be some heat gradient due to the ice touching the outside of the fish)

Doesn't not overcooking it also prevent overcooking?

don't we have more effective ways to seal in moisture and flavor than freezing fish in block of ice?

Yes. But not more effective ways of demonstrating this technology

If this technology is actually worth $10k, there should be a demonstration of an actually valuable cooking process with it. This contrived demo makes it feel less valuable than it might be (I don't really know if it's actually valuable...)

Scroll down. This is the first of ten examples.

But then I would just vacuum seal and cook sous vide with an immersion circulator which would cost 1/20th the price of this oven

Now I wonder about process of freezing fish inside block of ice. Does that affect the fish texture?

Modern fishing frequently does on-ship flash freezing and the results are often better than fresh fish. At least one reason is that the freezing kills parasites. But also the fish will stay viable longer.

The important detail is the method of freezing. Just tossing a fish into a regular freezer doesn't work. Flash freezing doesn't create large ice crystals which mess up the tissue.

Freezing is often worse than non-frozen but is actually fine for preserving freshness of fish. But actually putting a whole fish in an ice-block - I don't think anyone does that.

Surely it makes the fish crunchier.