Maybe it's just me but i'm not sure if the Blood oath is supposed to be treated as the highest law within the Horde.
I think obedience towards the (War)chief is a huge deal within the Horde, but i think it's also rather self evident that the Leader / Chieftain places the well being of the Clan / Horde above all else.
At the end of the day, disobedience or outright rebellion are pretty much outlawed everywhere and only the outcome of that conflict decides whether it was a "criminal" or "justified" action.