The difference between cheek augmentation through a cheek lift and fat filling is that in a cheek lift the cheek is mobilized from a lower position to a higher position, through a surgical procedure that involves two incisions: one on the scalp and another on the inside of the cheek.
Fat grafting for cheek augmentation consists of adding volume through your own fat, therefore there is no real elevation of the tissues, but rather that produced by the grafted volume itself.