Mafia 54. This is where caravans are robbed!

I didn't understand the point.

I think that if they were mafia members, their chat colleagues would have advised them not to write such things. Although, of course, that's not a certainty.
And the fact that Amko is an elf is also not a certainty, but it's very possible.
As for Gur and Ar vying for the same role, I'm judging this based on the commander's notes and another note – in this case, Ara is left with one world, while Guru has two. But Gur is more likely one of these roles than the other. Purely based on psychology.

Added 1 minute ago
And the idea that Amko was trying to pass himself off as the fourth one is a good one. But he was doing it so carefully that I don't know if there was an attempt.)