Forensic tests for urine stains would include using special lighting that makes body fluids glow in a dark room. Urine can be detected, contrary to Thomas' statement.

>>>A. Detective Trujillo imparted to me that he had learned or believed that there was not a presumptive test for urine according to the CBI.

http://www.mellesgriot.com/products/forensics/forensicstutorial.asp

"Detecting the presence of physiological (body) fluids: Forensic light sources may be used to detect the presence of blood, saliva, semen, urine, vaginal secretions, and sweat. The example below shows semen observed by using near-ultraviolet light."

If JonBenet's bed was freshly wet, on the morning of the 26th, even if it had dried by the time the sheets were collected, the urine stain would appear as a large, solid area under those lights. Even without special lighting, as noted above, the appearance and odor of fresh urine on the sheets the morning of the 26th would have been unmistakeable.

The CBI's microscopic analysis may have indicated the presence of creatine, but prior to that test, lighting would have used IMO.

Simply put, creatine is irrelevant if there were no visual or olfactory indicators, no apparent stains in crime scene photographs and no pool of urine observed under special lighting.