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From memory, I beleive the upper inner are the rear foglight sockets, will try to confirm that Thurs. Does your car have a switch for them? If the manual doesn't mention them, they may not have been included in that model type/year. Common with Volvos to have unused misc openings, many different configurations built around the globe.
For colors of sockets, just know I've fought enough bulb failure lights to just do it that way w/o question. If you look at them, the terminals that contact circuit board are probably "phased" differently, thus aligning the correct terminals, all important to function when concerning dual filament bulbs. They are made to be tamper resistant, but not foolproof. Also from here can't see if parts are aftermkt replacement, car in accident and rewired etc, so please supply as much info as can for accurate advise.
Hope this helps,