[Physicist]

I am not alone as a scientist and engineer to point out that if a theory requires as one of its foundation elements a probability function anywhere in its defining equations, then the necessary science behind the hypothesis is "incomplete" and unknowns exist that may extend and revise the current theory.

That was a viable position until Bell's Inequality came along. All possible local hidden variable models have been disproven by experiment. If quantum mechanics isn't complete, we can at least say with confidence that it is as complete a model as physical reality will permit.

[OBAFGKM]

All possible local hidden variable models have been disproven by experiment.

Not so. Bohm's pilot wave model is a perfectly viable hidden variable model. In fact, I seem to recall Bell having been influenced by it in deriving his theorem.