Yeah, there really isn't anything the dealer can do about it other than disconnect and reconnect the 12V battery to reset the latch - and you can do that just as easily on your own without the hassle of taking the car in.Careful with how you approach this. Most dealers will be hesitant to guarantee anything over the phone. They will likely want to diagnose it themselves before making any promises.
The important thing that needs to happen is for GM to understand that this is a problem so they can fix it. And the existence of the TSB seems to indicate that this has happened. Perhaps a lot of calls to the concierge might prompt them to bump up the priority of the fix....? But at this point I suspect that dealer service visits wouldn't be very fruitful.