Andor's Trail

Help in Fungi Panic's mission I can't finish, I've killed the enemy a few times, but in the last room the black tornado didn't come out, I handed the mushroom bag to the potion maker and he crushed them and didn't give the potions, no I know how to go on, old Bogsten doesn't say anything else, help me go on

Find another way into the cave. Maybe talk to Gison