I have an issue with causal determinism, not because it doesn't exist at all at any scale or in any system, but because, at a fundamental level, nature does not obey it. The behavior of quantum systems does not follow deterministic causal relations, but rather stochastic or probabilistic ones. As best as our understanding allow us to see, the observed uncertainty in quantum systems is not an issue of experimental limitations, but it is intrinsic to the physical dynamics itself.

In summary, to say that everything in the universe follows causal determinism is inaccurate. Thus, to try and build a line of reasoning about fate or free will based on the assumption of universal causal determinism seems fallacious to me.