The ID Ajax refers to the specialist:
Kerk's urban combat expertise was hard-won, fighting in the streets and alleys of the shanty towns that sprang up on the outskirts of Johannesburg in the early 2020's.
Increasing desertification had displaced millions of individuals as the continents' farmlands collapsed, creating brutally policed slums where the strongest gangs got the pick of the aid handouts while warring amongst themselves - and with the riot police who guarded the convoys distributing food and medical supplies.
When Van Graan, a self-styled warlord took over Kerk's gang, he fled, eventually establishing a militia of his own; one dedicated to looking after the needs of the people, rather than crushing them in its own self-interests.
Rossouw and his soldiers fund their operation by selling their services to the highest bidder.
- Kerk "Ajax" Rossouw - callofduty.fandom.com