I personally love the concept of Vasudans = Ancients; given how small GTVA space is it is much easier to explain the rise of 2 species within a rather small timeframe than of 3. However, it got me thinking too- if the GTVA (or just the Vasudans before that) would excavate Ancient sites and only find Vasudan skeletons, it'd pretty much tell the truth about the Vasudan-Ancient relationship.
While there might be political reasons for that (in particular when the HoL was still active) I doubt that such a discovery could be kept a secret forever. Or is it possibly an oversight that such a finding might be leaked, like with "wouldn't it be possible to have sublight communication to learn of Earths fate"?