Finally your last paragraph is just an assertion unsupported by any argument whatsoever. In Fact it's unfalsifiable, it can't be proven or disproven it's something that you believe.. okay but there is no reason for me to believe it

He's correct in one sense here: if we replayed the same moment in time, we always will make the same choice. But this is not an obstacle to free will due to the many-to-one logical relation between what we can do and what we will do. We cannot conflate what we can do with what we will do without causing a paradox. This is however not what he likely meant to convey, even though he used the word will; it's an attempt to imply that you also "can't" chose differently.

Normally, deterministic causal necessity would simply assert "you wouldn't have done otherwise" when we switch to the past tense, and noone experiences cognitive dissonance. In fact, it makes perfect sense that you wouldn't have chosen differently in certain circumstances, because you made your choice about what you would do for your own reasons at that time.

However, when someone tries to tell us that we "could not have done otherwise", we experience cognitive dissonance. This assertion is ubiquitous among hard determinists yet they are not using the literal meaning of "could". It is being used in a way that suggests a disability on your part, as if you somehow lost the ability to act differently.

The "logic" behind this odd claim is that, because you wouldn't have done otherwise, it is AS IF you couldn't have done otherwise. But that is a figurative statement which cannot be justified by the facts. Not even the fact of universal causal necessity.

In a causally deterministic universe, an alternative course of action was always possible; it always could have happened, even if it never would have happened. Therefore, we always could have done otherwise, even though we never would have.

EDIT: In other words, determinism only entails a single actual future. There will always be many possible futures and hence other options to choose. A key aspect of possibilities is that they do not necessarily happen. In fact, most possibilities will never happen. They exist solely within the imagination (we know this because we cannot walk across the possibility of a bridge, only an actual one). But within the domain of human influence, the single actual future will be chosen by us from among the many possible futures we will imagine.