It's more like 35-40% urine and 60-65% feces.

Any laxative would prevent hepatic recirculation but by using fiber you get a second benefit, redirection of some of the metabolites from urine to feces by way of absortion of bile acids. Do a search and you can find my more detailed explanations on both.

Creatine loading needs time to be effective. It takes your body 24-48 (closer to 48 for most people) hours to metabolize creatine to creatinine.