Gina,
I too am confused by the term "valet mode" with keyless entry/start like we have.
I think I can sort of understand it with the traditional keyed systems where people could disable the alarm and simply hand the valet the actual key to use to start, lock, etc. the car and not have to give them the alarm fob. But with the key FOB like we have...I'm not getting the true use of "valet" either...perhaps one of the folks can explain it to both of us...LOL
To be honest...if you are concerned about the FOB (with good reasons as they are expensive)...I think but I think if you leave the car running and you get OUT at the valet stand and keep the FOB with you the valet would be able to drive the car to the parking spot and push the button to STOP the car and use the manual on the door buttons to LOCK the car. When you come back that is when the valet would NEED the FOB to go unlock (well they could use the valet key) but unlock and START the car to bring it back to you.
My wife typically keeps the FOB in her purse...she'll get OUT of the car as I drop her off at the door and walks in while I park. While the car will "chime at you" that the key is not within the car...you can still drive it away. But before you push that button to turn it off...you better have all windows up, etc. because you can NOT restart it since you don't have the key FOB.
So...I think this would work for you if you didn't want to give up the FOB initially...but the problem may be at the valet how do they identify your car as they typically wrap the corresponding ticket to the keys...
Hope this helps.
Joe.