Without a stepper to hold the torque all the time, ballscrews will creep. The friction is too low. You could leave the ballscrew and just add a shaft locking c

Without a stepper to hold the torque all the time, ballscrews will creep. The friction is too low. You could leave the ballscrew and just add a shaft locking clamp, or be fancy and drive it with an actual stepper motor.