Ivan Griffin's campaign. Quest 2 (Power of the Unfulfilled) (Might and Magic: Heroes 7)

Actually the question is this. What to do with Andras Raven? It appears in the southeast of the map, and I don't understand how to get out of there. They can only move in a straight line back and forth, around the mountain. At the same time, they need to capture the mines and shoot from the catapult, but as I said, there is no passage to reach them. What to do with him?! In addition to him and Ivan himself, there is also Tanis (because in the previous task he chose her).