1. Solomon made it very clear that all mankind's whole duty is to fear God and keep his commandments (Eccl 12:13).
Beside the problems in your title and first argument, this first verse contains 2 commands to men; (1) to fear God and (2) to keep His commandments. These commands, which in effect are likely one command (fear God/obey God) are made to the volition of men.
So, you're telling us you're going to prove against men's free will, or volition, or ??, and begin by providing a verse that commands men's volition to choose or reject obedience to God.