Countess Dantalion's grand entrance may have been turned around, but without a doubt, she had bought enough time for Prince Stolas' troops to push to the frontline. The mages had also used this break to patch their shields for the next impact. They ensured that the safe zone was stable enough for formation organisation and for the commanders to take control over the battlefield.
The cultivators, while useful in delaying the advance, knew that it was inevitable that they could not hold down the enemy army. Otherwise, what kind of dungeon would this be if they could defeat the enemy at the first line? The cultivators were actually looking forward to getting beaten back and becoming more desperate before ultimately achieving a hard-earned victory.