1. Specter assaulted the city, and threatened the group.
2. Doomslayer spearheaded the assault against Specter, Hiro tagging with him.
3. Doomslayer took on the defenses with the slight support of Pegasus provided by Hiro as the Slayer distracted the defenses to let Hiro inside undetected.
4. Hiro witnessed weapons of war being manufactured, and human beings being used as slaves. He attempted to intervene, resulting in the deploy of Mecha Hiro.
5. Chief led the second group as Kale went to distract Specter's ship.
6. Hiro defeated Mecha Hiro just as Specter decided to negotiate with Kale.
7. Team Chief made it inside, and everyone regrouped to fight Caponek around the same time Specter issued his 'cease fire'.
FACT. Team Chief knows nothing of this compromise between Specter and Kale. Specter is simply trying to manipulate Kale into siding with him, but Kale is still in contact with Chief, unbeknownst to Specter.