Then my question remains, what could discredit determinism? Even if the evidences were strictly hypothetical, what, if anything, could discredit your concept of determinism? I can not answer that for you.
I think that according to my description and definition of determinism the only thing that would discredit it is a philosophical theory that proved God could not know the future, and yet still be eternal and perfect. Yet then I think we would have to tackle the idea of eternality...which I think is already an open discussion (God and Time).
How could we discern between a) an entity (of higher, lateral, or inferior power) who does know the outcome of all actions but does not communicate that information to us; and b) the nonexistence of an entity with the described foreknowledge?
First I would like to say that if the entity (of higher, lateral or inferior power) who does know the outcome of all actions were to communicate His knowledge to us it would not matter if that being was perfect and incapable of error.
You see within the Christian teaching if God does know the future, and if He is perfect (incapable of knowing that which is false and incapable of being false) then His knowledge of the future acts of man would not necessarily 'force' man to make what God knows he will make; yet it would make it so that his it is logically necessary that he do that which God knew he would do.
Other than that I think that it boils down to the idea of whether or not you choose to believe option A or option B. I would opt for A, you would most likely opt for B. Perhaps our discussion must then evolve into discussing how to prove which one is true, yet I think that is an unattractive option.
That only a single chain of results happens (out of what appears to the casual observer as many possibilities) does not, as far as I can tell, imply that the unrealized possibilities were impossible prior to the decision. That is, those unrecognized possibilities could have been recognized; they were real possibilities, not illusions.
That only a single chain of results happens (determinism in the sense of Hawkins determism) would not, as far as I can tell either, imply that the unrealized possibilities were impossible prior to the decision.
YET, if only a single chain of results happens, and those results are known by an infinate and perfect God, this would, as far as I can tell, imply that the unrealized possibilities were impossible prior to the decision.
As if I were going to choose A, and a perfect God knew I would choose A; then I must choose A as the perfect God could not be wrong. If I were just as capable to choose both A and B the perfect God could not know that I would choose A, rather He would have to know that I 'could' choose either A or B. He could not know my future choice if both possibilities were as real as each other.
One of the implications of strict determinism is its inconsistency with my will, which displays all of the symptoms of being under my jurisdiction; that is, when the options appear to be equivalently weighted, I assume they are equivalently weighted. However, in exercising my will, I accept the irreverseability of the decision.
I would argue that the strict determinism (in the perfect God sense) would not be inconsistent with your will. You can will A even if a perfect God knew you would will A. You would still be the one willing it.
I would even go as far to say that this form of strict determinism would not be inconsistent with even a free-will. Granted the perfect God's knowledge of your willed decision made it so that your will was logically bound to do that which it would do, yet it still did it; it was not forced by outside forces. It was not with complete freedom (able to will to be a bird or cat...) yet it was not completely hindered either.
I would however state that this form of strict determinism is inconsistent with your free-choice. Able to equally choose both option A or option B.
Perhaps for the purpose of this discussion, we might start with the following definitions:
determinism: the belief that all outcomes are fixed, settled, or known in advance.
indeterminism: the belief that all outcomes are not fixed, settled, or known in advance.
The next question might be something like, "Is the set of that which is 'known in advance' limited to human knowledge?"
I would first state that right now I think these definitions are quite satisfactory. Although I would state that these definitions, in my opinion, do not consider the form of determinism that would be posited by secular (those who do not believe in God...atheist/agnostic/physicist

). Because they would state, would they not, that a certain particle acting in a certain way will spin off a certain universe, and if this particle had acted in another way, another certain universe would be. Would this not be a form of determinism?
I would also say that the question is great, I do not think it would be the next logical one. As we have already discussed certain theories as the Heisenberg uncertainty principle; I would then think to discuss whether this principle disqualified the definition given of determinism.
If the Heisenberg uncertainty principle is indeed true, it would disqualify the kind of determinism that I mentioned two paragraphs above (the universe spinning off of the action of a particle); yet I do not think it would disqualify our definition of determism.
Consider this. The principle proves that the outcome of every equation is not always the same (and I say equation to speak as an ignorant man towards these principles. I mean when an atom combines with another; then an exact outcome is always produced. The principle would prove this idea false). If this principle proves this idea false, it would not disagree with our definition.
As our definition states that the outcomes are fixed; fixed by what, that is for future discussion. Yet we can state that they are fixed by the knowledge of a perfect being (as I have posited) and yet not disagree with the Heisenberg uncertainty principle as the outcomes are not fixed by some natural law (which would, methinks, reek of the Christian idea of Miracles: the dead do not always stay dead, man does not always sink when upon water...

)
Understand?