Just because actions are predictable and based in natural, universal law does not mean there is no free will. There is an underlying free will within the source of all universal laws to begin with. This "law" is love and attraction, free will, which starts on the subatomic level. This law of love is rooted in our longing to re-unite. It is misguided in its action but not in its intention, and makes all of material life possible. Example being the hope to unite in love and ending up multiplying - so two do not become one, but three, four, five, six etc. In other words - this re-union cannot happen on the material plane.
God's will (if you believe in God), and our free will (if you believe in us as separate from God) are just two versions of the same end goal of re-union. We assume that time and space - and with it separation - exists, which in truth they don't. Only to us they do. So we worry about things like "free will" and "God's will". "In truth" - there is neither "God's will" nor our "free will". The whole idea of "will" is a very human idea and invention and based on the desire to manipulate the material world. "No will" is "God's will" if we want to be precise - in other words, total peace.
In our illusion - time/space existence - omniscience and free will do co-exist, but it is a paradox. Paradox - is not illogical, but the highest level of logical insight that can be reached. The distinction between "paradoxical" and "illogical" is vast. Paradoxical insight is wisdom. Lack of logic is simply stupidity. Then there is a third way. If people who do not have the ability for paradoxical insight trust a person who does - they can just have faith. It only gets silly when they try to argue points of faith with a logician, who has not reached the level of paradoxical insight through the disciplined pursuit of truth by logic and experiment. Then it is a situation of the blind arguing with the blind.