Yes, it's an allied realm.
I don't think so, but would that make a difference anyway? The issue is not that the diplomatic actions as a whole are having little effect (although that is also the case), but that each individual attempt is failing. Whatever dice roll is used to determine if the specific diplomatic action succeeds (or at least has a greater effect than the worst possible result) is failing every time.
I don't really know how the snippets of text relates to effect. I think it's possible that the "They seem unimpressed" relates to their final view of the realm and not only to the change you achieved.
