Sticky stuff on dash and other interior things like buttons, button covers can be removed but it takes time. Toyota Camry, Mercedes Benz, Subaru, and BMW use a coating on interior components as UV protection it also gives plastic more durability against wear and tear and gives it a matt finish, but after time it break's down. Using armor-all or other products like it that produce a shine finish "to protect actually are bad for your vehicle.
Unfortunately I see this problem fairly often in Florida. As far as I know there is no way to repair or fix the dash when it gets like that. Replacement may be the only option however being that's it been recalled and it's over ten years old that could be difficult to do. Maby check with the suburu parts department. Sorry I couldn't be more help. Good luck.
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