Okay so some possible scenarios from my perspective.
1) Arch is Hitler, randomly investigates a fascist. He doesn't want to out a fascist for no reason, so he claims liberal, of course. Egor's play in this situation seems super risky though, he doesn't want Hitler involved in a counterclaim, surely? So I think this one is unlikely.
2) Arch is a fascist, investigates Hitler, declares him Liberal. This makes sense as a fascist play, especially since people were suggesting the investigation to begin with. But then Egor playing a fascist here seems crazy. This seems unlikely as well.
3) Both are regular fascist. This sounds most plausible to me. Egor makes a bold play, with the intent of making one of the more active players look scummy and hopefully making him and his buddy look better. It's risky, but has a good chance to pay off.
So... okay. I don't think Arch or Egor is Hitler, probably. Unless we're going one level deeper of crazy play, at least. That means there's still one more regular fascist out there, and Hitler.
Who voted this proposal up and who said no, that's what I think I'll look at next. Although it'll be over an hour before I can post again since I'm heading out very soon (this is basically a self reminder note, in case you're wondering).
PPE 3 - I haven't thought about investigation target yet. I'll think about that later. I agree this is potentially a good result though, getting scum in counterclaims is powerful, although it's a bit frustrating to be involved in it myself (I've always preferred deducing information rather than arguing my own corner).
PPE 1 - I want to get off Mr. PPE's wild ride