Hooray! I'm glad to know I managed to finish the whole tree. I'll definitely come back and do it officially after the patch is out!
[SPOILERS BELOW]
FYI, I tried starting a new game, and I was able to get Ketini to count towards a correct set of three, but I still couldn't get Kenit and Avina working. So if you're looking for a source of the bug, I'd start with those two.
RE: "Explaining Death"
Ahhh, now I see, thanks for the explanation! In retrospect, it makes sense that "he" was Selinar. I think you're right that making the document appear later would be helpful, because with the information I had when I first saw Explaining Death, my thought process was:
1. Mercian says "they (Miveen and Ovith) sed you are ded".
2. Rivanel's letter says "You dared tell my son the news... He did not simply die, Miveen."
3. Therefore, Vilan is male.
In retrospect, I assume Mercian's drawing is meant to imply Vilan is female (long hair and dress). But with textual evidence of "his" gender, I just accepted that Vilan was a man with long hair wearing a robe. This is especially because, at that point, I didn't know enough about Merrithean society to see how they expect men and women to dress and do their hair.
Even once I knew that, I just assumed that Vilan's hair had grown out because "he" was trapped in a room for who knows how long, and that he was wearing a gown, like an ill person in a hospital might today, to make it easier to take care of him.
That doesn't make a whole lot of sense in retrospect, because it assumes that Mercian has either seen Vilan recently, that someone gave him a detailed account of how Vilan looks nowadays, or that he understands things like "Meltormated folks get trapped in rooms for years with very little care, so they may not get their hair cut." All of those seem unlikely. But I wanted to give you my thought process anyways, in case it's interesting or helpful!
Good luck to you as well! I look forward to seeing more of your work -- maybe we'll even end up in the same game jam at some point!