The front and rear calipers on these SUVs are very, very different animals. Front is the more modern (and better) "Colette" design, where a short bolt attaches the guide pin to the housing ear, and the length of the guide pins slide directly into the bracket bores during assembly and in-use. For this, moderate lubrication of the pin/bore interface is needed, and a little excess will simply squish out into the dust boots.
But the rears are old-school RPS design (Reverse Pin Slide). As the OP said, there is a long metal sleeve involved, that the other design does not have. This sleeve is completely contained within the long, convoluted rubber boot, both of which are squeezed thru the housing ear. The main sliding lubrication in this case is needed between the metal sleeve and the rubber boot, NOT between the pin-bolt and the sleeve. The pin-bolt simply goes thru the sleeve, and threads into the bracket, clamping the sleeve securely to the bracket. The sliding occurs between the housing ears and the bushing/sleeve. Any lubrication between the pin-bolt and the sleeve will simply be along for the ride. A very thin film-coat would not hurt anything, but is not necessary for caliper function.