I'm going to guess that we'll probably learn more about the two of them in the expansion. Raubahn is featured in the opening cinematic for the expansion, so he is still going to be a key player even being imprisoned. There will probably be flashbacks or something to talk about their meeting. Like you said, it is a very important point to his character and the path he went.

There's some interesting things people pointed out. The arm he lost, is apparently the same one that he held Nanamo up in during ceremonies. And strangely enough, his Triad card actually has a terrible number on the same side that he lost his arm.

Given that Ul'dah is now on the edge of civil war, depending on how things play out. The adventurer's best move is to do nothing. Doing something only makes you look guilty as we all know in stories, especially when you're innocent. And starting a civil war is also not something the adventurer wants. So it seems like they're being an idiot, but the adventurer isn't dumb. They understand politics and the situation well enough to not act rashly.