I haven't tested it since the recent patch but it should work the same. I'll probably get around to it today as I'll use it in a mission I am creating. As for Asymmetric, I am guessing they are setting up depot's there because it is considered abandoned if nobody is there. If it's defended it will probably be treated as an assault objective first so the insurgents can capture it. Just a note too, if you are using the AAF/resistance side for the insurgents.. the code needs a slight change since it only registers it as an objective to EAST and WEST in it's current state.. Here is a fixed version that will register it as an objective to all sides: http://pastebin.com/dBQQVP0n

In terms of it being recognized as a blufor held objective, this kind of goes along with it being defended. As far as what I have learned is that a side "controls" a location if they have dominance in force strength so if you send units to defend the FOB ( or opcom does) then it should be recognized as a blufor base.

Edit: Simpler way to put it, having blufor near/in the fob will raise the hostility levels which then has an effect on what orders the insurgents will use to react to it. They may assault it or choose to ignore it if possible. If it is empty of bluefor then they may choose to take it over themselves and setup a depot.