The title here seems very different from the post. All that verification happens locally only. There's no remote validation at any point. So I'm not sure what's the reason to even apply this check. If you're running the model yourself, you know what you're downloading and can check the hash once for transfer problems. Then you can do different things for preventing storage bitrot. But you're not proving anything to your users this way.

You'd need to run a full, public system image with known attestation keys and return some kind of signed response with every request to do that. Which is not impossible, but the remote part seems to be completely missing from the description.