The "Reverse" function should be f10 under the Custom Settings menu, it should not be in the Shooting Menu. Can you access the Custom Settings menu and find f10 "Reverse?" If this same function is showing up in 2 places (and especially since it appears to be replacing "ISO Sensitivity Settings" in the Shooting Menu) there is likely something corrupt in your camera firmware. There is no way that the "Reverse" function should be showing up in two different menu systems.
If this is the case, you could try to reinstall the latest firmware (same procedure as you previously used to update to this version), or you could send the cameras to an authorized Nikon repair facility.