I think your car GPS needs updated maps. This is not a state secret but it's also not widely known-- the location of that cave doesn't show up on most GPS receivers; instead you get redirected to the nearest red light district in order to distract all the intelligence agents. The only way to find out the true location of that cave and that address is to follow all the sheep humpers and see where they go in their search for sheep. Or so I'm told. It may just be a kasbah myth for all we know.