His VOA shows the oil labelled as SF, which appeared in 1980.
And no, apparently Mobil 1, from the get-go, was PAO/Ester until Tri-Syn happened. That was from TomNJ, who I believe supplied the esters at the time through Hatco, so he'd know. They may not have had the balance right in the first few years though, based on the claims of it causing leaks (possibly due to PAO seal shrink, but that's just speculation on my part).
On the Valvoline, that's Synpower Racing Oil, it could very well have some ester in it as well, like 300V for example. Yes, the water should still condemn it, my point is that we don't know what virgin oxidation is for any of these oils and given the known impact ester content has on this, claims that this is a reliable metric are dubious at best.
Another data point: The gear oil had an oxidation figure of only 6.1, so if this was true oxidation, why was it exempt?