It takes a little time (fightings and researchs) in the swamps, to find the witch.
And for the acolites, you have to wait for Othra to give you the quest, and then go to the pond in the forest (you need to fight a nymph), another in the swamps (you have to save her from the corrupt warriors), and the other must be released from the Lizards warriors who hold her hidden where they do their training.