EXACTLY, & what we know is that Vergil hungers for power, we don't know whether he sleeps with women or not, so we can't just assume he doesn't have sex just because he wants power, those two things are completely different. you just made my point more clear, we can't assume that Vergil's character is "I want more power", & nothing else, we know that aspect only, & being power hungry & having sex aren't contradictory events either.
Given that this is a game we are talking about, and not a reality, we definitely can assume that Vergil does not have sex. And, there is a well established occult connection between sex and power as well.
My point is that we can't assume based on what we don't know. So we can't assume that Vergil impregnated a women over his established character in the game and manga. There are few if any scenarios that would work out without contradicting that established character. Again, not impossible, but possibility is a moot point here.
as I said, what he knew wasn't enough, maybe he just speculated, he ordered Credo to arrest Nero as soon as Agnus confirmed it. & maybe he did know, but they can't clone Vergil & have a mysterious POWERFUL arm that even Vergil didn't have, & why would they clone Nero & then throw him out, just to be found later by Credo & Kyrie, there are a lot of reasons, not just whether Sanctus knows that Nero has Sparda's blood or not.
No, he definitely KNEW already. He may not have known that Nero had the DB, but he definitely knew Nero was from Sparda.
If the DB is an issue for the clone theory, then it totally blows the son theory out of the water. As for why they threw him out to be raised by an orphanage, well, that would erase the trail of evidence, and it is much safer than raising him in captivity.