Cinderella Potty Pez

My daughter loves Pez and this is her favorite dispenser. Hubby and I were thinking about ways to motivate her into wanting to go on the potty all.the.time instead of when she feels like it. She started off training with a bang, doing real well and we thought this would be easy. But alas, months later she is still pooping in her diaper.
We crack out Miss Pez last night after dinner and her eyes lit up, she's a real die-hard Pez fan. So we think we hit the jackpot with the candy bribery reinforcement. We explain that when she goes pee she gets 1 Pez and for Poop she gets 3. Well, she didn't get it at first.
"But I want her"
"I need her"
"Cinderella isn't going Potty"
We explain that is HER who needs to go potty to get some Pez. Then she asks if Cinderella Potty can can watch her go potty. We tell her sure and she proceeds to go sit on the throne. Ten minutes later she announces that she is done and has peed and pooped. On closer inspection, she has done neither. So no Cinderella Potty Pez for her. Meanwhile (as a non-thinking bad parent does), Z is diving into his Pez that we let him have while E gets none. Of course she gives us those eyes - you know the ones, and we explain that Cinderella Potty Pez only pays out for Big Girls who actually go on the potty and not just talk about it. So, no Pez for E. But she did go potty this morning when we got her up. I kept my word and Miss E had 1 Pez for breakfast. We'll see how this goes. Wish is luck!