If you have the VIP Pass on Rock the Cradle, all private areas of the heist essentially become public areas. Cameras and guards do not detect you in casing mode in the VIP area of the nightclub, or in any other private area on the heist. Secure areas work as normal, of course.
In the searching phase, guards do not normally detect you in casing mode in public areas still, but will instantly arrest you in private areas. Does this same logic apply to the private areas of Rock the Cradle with the VIP pass? Or does a searching phase while the crew is down in the VIP area mean certain doom?