Any time you can get rid of an odor with minimal labor, you're a hero in the customer's eyes. ClO2 makes it almost TOO easy. Some of my guys feel kinda bad for charging as much as they do, lol, and then some are whistling cheerfully on their way to the bank.
If you've bleached a carpet with ClO2, you're doing it wrong. I've used it multiple times in both its gaseous and liquid forms, and have never bleached out anything.
However, it IS lethal if used incorrectly, so it's not a tool I'd recommend in just anyone's toolbox.