Hunters from the Sons of the Moon guild had arrived at the dungeon prior to the decided time. Despite the exaggerated tales of their illicit activities, they were a bunch of simpletons in a good way.
Obviously, Adrian had done his research about them as soon as John asked his team to participate in the joint exercise. He wasn't taking any chances after what happened with Lucas and Felicia.
He was even more careful about them because they had links with Lucas and Felicia, which meant they could as well turn against him. Thankfully, that wasn't the case.
But he did find something interesting. The White Tiger Clan seemed to have been active in Hawaii for quite some time, but they disappeared right around the time Vernian struck their convoy.