Or that he really really wanted to prepare something else in his fifth-level domain slot. Not that Nergal granting the Air domain, despite his wings, is terribly likely.
On another note, it looks like a full-fledged fight is developing, which is another opportunity to tally damage! So far we have:
6d6 acid + 6d6 acid + 9d6 acid + 6d6-30 acid + 9d6-30 acid + 9d6-30 acid + 3d6 falling (24-198)
6d6 acid + 6d6 acid + 9d6 acid + 6d6-30 acid + 9d6-30 acid + 9d6-30 acid + 3d6 falling (24-198)
6d6 acid + 6d6 acid + 9d6 acid + 6d6-30 acid + 9d6-30 acid + 9d6-30 acid + 3d6 falling (24-198)
9d6 acid + 9d6-30 acid + 9d6-30 acid + 3d6 falling (12-120)
3d6 falling (3-18)
7d6 falling/bludgeoning (7-42)
The source of the acid damage is obvious. As for the falling damage, the highest a Carpet of Flying, with its 40 ft. fly speed and average maneuverability, can fly in one round is 35 feet.
V's total damage is 7d6 because rock crushing traps and pit traps deal damage expressed in d6s, and her minimum HP total at level 15 total is 39.