Though if the aliens were planning well, they would have been best to stay quiet and win due to indecision...
Maybe that would have been too boring/easy for them so they just decided to stir things up?
But yeah, 9 times out of 10, the real aliens would have just done nothing as the odds are on their side from the start.
The fact that Privateer Puddin' is only doing this whole "I'm the real Psychic" thing due to the dubious claim that the aliens have PM'd someone pretending to be the Psychic makes me think it's very unlikely that this is what is really going on.
The simplest answer is that Privateer Puddin' got busted by the Psychic and is doing the last ditch claim of power role (quite well too) to escape death.
Now, why would the Psychic trust just anyone to PM and relate the info to?
Well, how else would they get the info out?
The good side needs the info to survive or it's game over.
The Psychic can either come out on their own and tell it, which is an immediate death sentence knowing that the Doctor is dead.
OR the Psychic can contact someone out of the blue to reveal it and have a chance of hitting a good team member and then the info gets out.
OR they might hit a scum team member and if that person doesn't post the info the Psychic can come forward before the end of the day exposing BOTH scum members and hope there is enough time for votes to come in.
SO I'd say it's at least 80% that Privateer Puddin' IS scum.
Kastchey probably isn't scum, but could be scum and be just throwing his team member under the bus, or could even be the real Psychic using a ploy to hide detection, although I'd think he is smart enough to PM someone else if that was the case as in the above-mentioned scenario.
OR I could be completely wrong and we just lose the game right here and now, who knows in a game with this few members, but I think the odds are on our side.