I actually had this happen in downtown Portland, OR at the Heathman Hotel. The hotel did not have self-parking and I didn't have a choice but to use the valet. When they brought the car out front for me and opened the driver's door into traffic and right into a bicyclist. There was minor damage to the car door but at least thecyclist was not hurt.
Anyway, I reported the incident to National and was told that a hotel or restaurant valet is an "authorized driver". I did take the name of the valet and details of the accident along with the hotel managers's name and phone number. But I never heard anything more.