Makes little to no sense, really. I suspect maybe Nicolai had secret orders to kill of S.T.A.R.S. operatives for Umbrella's sake, retained information on Jill's whereabouts, placed a detenator inside of Jill's apartment and attempted to murder her in what appeared to be an accident. But thats just all speculation.At the beginning of Re3, where Jill for some reason gets blown out of front door of her flat building. I reckon there should of been a playable part before that happens, where you begin in Jills flat and you go downstairs to the front lobby.