So, apparently that wyvern was well known to the surrounding leadership, and they kept an eye on it just in case it headed toward their areas?
And... if it did, they'd have to mobilize at the same level as an all-out war in order to deal with it?
So... yeah, I can see why they might be just a tad worried about his intentions, given the ease with which he took it down.
Overtures of a peaceful nature might be a Good Idea™...
Way overpowered artifact.
Way overpowered wish for a peaceful existence; it appears to have the potential for establishing World Peace™ as an unintended side effect.