For some reason I maintain the belief that Capcom is content to pretend DMC2 never happened and doesn't exist and DMC4 is for all intents and purposes a true sequel. If they ever come out and admit as much, I wouldn't be surprised, I mean.
Still - if that's not the case, and they do intend on re-releasing DMC2 with an updated story/graphics and what have you at some point(though here's hoping they give the re-release attention to DMC 1 first...) then I agree completely. I can imagine several things that could of done this to him. Especially with the introduction of Nero. (I dunno, I sensed a sort of mentor thing forming there somehow.)
I'd be curious to see what they come up with.
But I won't hold my breath. ^^;