Sure, we could wait for the viz translation but I disagree on this possibility; we know that Kaido ruled this country with fear and power. He is not like Doflamingo who did countless business with other countries or the WG and did everything on the shadow. His only well known business is with Doflamingo - and it was to his own interest since he improved his military power with the smiles. Afaik, only Orochi made some business with the WG - and he used Kaido's name to threat them.
I am sure that Kaido was feared because of his power. That's basically his entire character. He is not cunning or a huge mastermind like other antagonists - he rules by sheer power. He didn't need massive schemes to take over a country, he took it by force (on the other hand, Oden could stop him but he was being stupid in this entire situation).