- For Vampire's challenge, you only have to survive for long enough. The bat will eventually run away, and you get the reward without having to finish the fight. That's why there is no usual "victory" screen with the rewards.
- If you escaped from one of the ogre fights, the hexagon should still be on the floor and allow you to do the battle again. You need to win all three battles to finish the challenge. If there is no more hexagon, you might have solved the challenge. Then you might be missing one of the other challenges.