What indeterminism actually does is makes test-cases into an unreliable form of evidence.

I don't think you said what you mean.

indeterminism

noun
Definition:

theory that some actions are undetermined: the philosophical theory that human beings have free will and their actions are not always and completely determined by previous events.

But that is pretty much beside the point, because

• You have provided no reasons why I should think that what you meant is true.

• We are not talking about increasing confidence in a system by testing it. Certainly Eliezer is not talking about 'test-cases'. We are talking about proofs of correctness.