No, there certainly will be a new ruler. The burning question is whether he'll able to keep the throne.
Leopold is surely walking a thin line. Trying to do things his own way but simultaneously ensuring that no crusade is announced can be a hard job. It remains to be seen whether he can truly unite the ex-Niselur lands, or whether will Gaston's refusal to follow him cause a greater rift that might spark a long term civil war.
