After the mother produces a flower and then fruit, it slowly dies off. At the base of the plant is the corm. Or bulb. The bulb does not die(in most cases) It produces what are called pups( baby or younger plants) from the same corm.In your case its hard to say what to do.There are quite a few experts here that could give you a full expert answer. I just do not see how the fruit can grow and ripen with no heat/sun to fuel them. Not to mention no water. But i would think that maybe there is enough energy in the p-stem(trunk) and corm(bulb) to keep them growing. But them again if they do ripen you may lose the corm due to the fact that it would be spent trying to ripen the fruit. So its a tuff call. As for bananas in pots. Most bananas just grow to big to be in pots there whole life. The dwarf and a few other species do well in pots. But the reason you may see many bananas in pots is because people in the much colder zones have no choice. Gets to cold to put them in the ground year round. I think people forget that bananas are very tropical. In most cases. But then again, that is why we grow them. We love tropical plants.