I attempted to replicate some of what I thought were the more interesting results, and my results differ from yours in a few cases, so I was hoping you could post the bots you used.
I have Margrave beating Library (~49-42), and I have Vault beating Noble Brigand (~54-42).
I didn't put any effort into optimizing VP card buys, so that might be the difference (I could see Library maybe beating Margrave via early VP buys, counting on the filtering from Margrave to get them out of the way). I just took the default bots with Margrave buying 2, Library 3, Vault unlimited (but 1 above Gold), and Noble Brigand 4. I also tried messing around with limiting number of NBs based on amount of treasure, but couldn't really find something that beat Vault.