No more bickering please. Argumentative posts have been deleted. I do not want to close this thread but if the arguing continues, I will do so.
Will a bala die if not kept with other balas? No, probably not (unless the cichlids go after it, and there's no way to know beforehand whether that will happen). Will it exhibit the same behavior as a bala kept in a group, in a tank large enough for a group? No, probably not.
Ultimately it is your tank and your decision, but it's not something I would try either in a 55 gallon, or with a group of mixed Africans.