These few people were already members of the Saint Race, but they also understood the vast difference between the Great Ascension and the Joined Bodies. Once one enters the Great Ascension path, the disparity in divine skills is immense, far beyond the small gap between the Void and Joined Bodies.
Under normal circumstances, a few peak Void stages joining forces can fight against an early Join Bodies stage. However, several peak Joined Bodies beings have no choice but to flee in the face of an early Great Ascension.
Because once entering the Great Ascension, one is considered half a True Immortal, capable of comprehending some incredibly powerful Heaven and Earth Laws during cultivation, which is something Joined Bodies beings cannot contend with. As for the final Tribulation Stage, it's merely a nominal division. Aside from a slight qualitative change in cultivation mana, divine skills do not increase much beyond the Great Ascension peak.