Free will means that the actual names that wind up in the Book of Life will be determined by chance. Some will choose, some won't. How does an omnipotent God leaving the eternal salvation or not of His most beloved creation up to utter chance glorify Him? True glory to God would be for ALL of His children to be with Him for eternity according to His accomplishment of His own perfect plan. Random chance cannot play a role in glory going to God. It would make no sense. Is deserved glory ever gained by accident?