The IGA vanias storyline is confusing, and almost crap.
For example, about OOE, it seems hat that Dracula's vessel was done by the 360/PS3 game, because in SOTN, Dracula isn't sealed anywhere, and we don't have any information about it. About the war (1999) we don't have anything but the ending, about the lost belmont blood, nothing, about the future of trevor, hector and Shanoa, nothing, about how the Belnades surname could pass to a child from its mother, nothing.
Castlevania seems to have a big universe since IGA is here, but, the major plot, is fractioned, or incompleted, or lost.