I think you have done the best you could and there wasn’t any more that you could’ve done. Kids will always find a way to do things behind your back, and it doesn’t matter what rules you impose. I quite like the way you handled it and how you said she should be more careful not to get caught instead. That sounds like you’re subtly opening a means of communication, and she will learn to trust you enough to open up on her own accord as she grows up. At least, that’s how I’d like things to be with my children when they reach that age.