Lets just be honest, Kaido was essentially irrelevant on a global scale, aside from being a Seastone salesman to the WG. the WG allowed their top contractor and scientist to live near Kaidos home. This is because they see him as someone who would be a good neighbor and would probably not actually start a global war(it would be insane to think he would after running from Shanks). In Elbaf, the giants never really dealt with or worried about Kaido, who lives pretty close by. Even when Whitebeard died, Kaido gained zero territories, while Big Mom and Blackbeard gained new ones.... Based on the canon manga, the beast pirates only ever had 2 territories.