Our American fridge freezer stopped cooling the freezer to cold enough temperatures after 16 years


I just need help on a couple of points.
I was thinking of cutting some of the wall between the fridge and the freezer off, leaving enough for the 2 doors to shut onto, so that the whole unit can be at the same temperature which will be controlled by a STC1000, but what I am unsure about is if there are any “gas” pipes in that wall. Would anyone know if Samsung run any pipes or anything I shouldn’t cut out in the partition wall?
Secondly, with the current fault/ malfunction of the fridge, is it worth me spending time and money on this project or is the fridge freezer on its way out and will not last much longer the a few months/years? I don’t want to invest all the effort into the project for the freezer to stop cooling after a few months.
Many thanks for your help in advance.
Paresh