Singjenn,
I also have had a similar problem with my '05 G6 GT. It has never been completely dead like yours has, but once every 10 starts or so the engine will crank and not start and I have to do it a second time and press the gas and it will start up. While it was under warrantee I two took it to the dealership and received the same "can not duplicate" answer. They did tell me something I never knew though, which may interest you. If you didn't know, this car has an electronic ignition system that is different from most cars. It does not require you to start the car by holding the key over. All you have to do is turn to on and let go and the car computers will do the rest. The dealership believed my holding it like a normal car was causing my start up problem. While this was not the case, maybe it could help you.
I also have had a similar problem with my '05 G6 GT. It has never been completely dead like yours has, but once every 10 starts or so the engine will crank and not start and I have to do it a second time and press the gas and it will start up. While it was under warrantee I two took it to the dealership and received the same "can not duplicate" answer. They did tell me something I never knew though, which may interest you. If you didn't know, this car has an electronic ignition system that is different from most cars. It does not require you to start the car by holding the key over. All you have to do is turn to on and let go and the car computers will do the rest. The dealership believed my holding it like a normal car was causing my start up problem. While this was not the case, maybe it could help you.