The divine beasts did not persist for long... To them, the other side of the Alamir Mountain was not within the original territorial boundary of Kalinsan.
For these elemental giants with a strong sense of territoriality, as long as their own territory is not violated, there's no need to risk their lives for expansion... Even though the crystal cores of those unfortunate beasts that perished were quickly collected by their companions... In order to save these guys, the divine beasts even paid an extra life.
As for the air god creatures, those who died were the little ones transformed by the Element Mages... The power of Meteor Fire Rain was quite large, so the large air god creatures didn't approach that section of the wall too closely, thus avoiding the pain of being immobilized to death... If the subordinates who took refuge die, so be it, it's not like they can't resurrect, just a few thousand years of slumber.