You can't talk to the Lizard or Imp, but I'm pretty sure those are the positions they'd take. This decision was presented like this because it's part of Scarlett's story arc, not a random political decision. There are other parts of different General's arcs where you make decisions at the requests of generals that might otherwise have come up for a council vote. The council is there to advise only. In the words of Terry Pratchett, it's a 1 man, 1 vote system. As Emperor, you are the man, and you have the vote.
It's true that Larian could have done this differently, maybe had the player be non-committal to Scarlett, but only allow the council to meet and present their arguments, so you could vote once you had talked to her. That would also have been a valid way to handle it. But that's not what they did. Oh well.
Oberon has a wife, it's mentioned in one of the other council sessions.
