Well....
I think I've figured out the problem in both cases.
The short answer: Tane's not smart enough.
The longer answer: There are standardized steps and checks in the quest system which look for low intelligence, for the purpose of altering the dialog slightly (mostly in what the PC can say). In these cases, the checks only look for normal or above intelligence, and there's no dialog options for low intelligence, which therefore means also that Tane is not presented with those options, and therefore gets only the "end" options by default, which keeps him from progressing through the tree.
Anyway, whether that made sense or not, I should have that corrected for the next update....the dialog problem, not Tane's intelligence. *winks*