Hey, sorry you're having trouble with the PS2 version of CSI. We didn't work on that PS2 port so there may be some funky logic that's not in the walkthroughs for the pc game. We're not sure what they did to make the game work on that system. I wish I could help more!
I would suggest you try looking for other evidence at the crime scene, or using the hints. They may have changed the hint to be more accurate to what you are supposed to do.