Would it not be a better suggestion, to just ask for the Toad mount to be added as a reward from a achievement or a dungeon drop, instead of tied to a Job? The Job mounts are meant to encourage players to play certain roles (tank and healer) which are not played by alot of players, the DPS role does not suffer from lack of players willing to play that role.

This is why I think adding it via a dungeon or other manner that is not related to the Ninja Job would increase the odds of this mount being added in the game.