It's complicated
Harald wanted to leave behind the times of pillaging and violence towards other nations. In his eyes, allying with the WG and becoming a member state was necessary to achieve this goal BUT the WG never saw it that way, to them Elbaf's war like strength was an asset. The WG's true nature was hidden to Harald so ultimately, he had to fail. As long as the WG exists in its current state there was no way the different nations couldtruly be allied on their own terms. Remember Harald's reaction to finding out about the WG? He saw they were in the way of free travel and free cultural exchange.
For Harald's dream to become reality the WG needs to go which only is possible in the current timeline. Rocks was not the right man for this, he was a violent pirate that pillaged.