For the Selvaggians that got defeated, they were not killed as they returned back to their sanity. They also do not hear the voice calling out to them anymore as well. Adrian and Levin Cloud could not easily send them back to their respective clans as they might try something again which is why Adrian created a quest.
Generating quests is something an owner of a territory could do as well as long as they can provide a reward. The rewards for the quest to escort the defeated Selvaggian race member are none other than talismans that Adrian crafted in his spare time. He barely uses the rare tier talismans, so he decided to use them as rewards instead.
The players thought that they will never see Equinox create missions as some players that own territories have created mission the moment, they are able to. The fact that Equinox is late despite being the first one to get a territory is shocking to them, but the rewards shocked them even greater.