Ugh, I wish she'd just poop and get it over with!!! I just sat outside with her repeating "Go Potty" over and over. She pee'd once then squatted and stared at me quite a few times. (She's learned to fool me by pretending to go pee just so she can go back inside the pool area and swim. )
My dad told me she didn't poop when I was at work either. I don't think she would eat a tennis ball. There isn't any evidence that she did. She's not much of a chewer anyhow.