It's a nice twist. I find the idea of having to keep your character (or a character) in frame of the camera intriguing. I think you could still have an interesting mechanic removing the dual controls. The "turtle" (now AI based, instead of player controlled) is some famous dungeon crawler and you've been hired to capture his crawling exploits. He gets angry the less centered he is in frame and when completely out of frame you are fired - game over. I'm can't wait to try out your execution.