After Jack endured all the injuries from fighting against an army worth of powerful individuals on steroids, plus two superior characters, Jinbe can only win against a heavily nerfed Jack.
And even then, it's not clear whether Jinbe solos him or not.
No, it's nothing but your headcanon. This chapter just massively dehypes Doflamingo again. At this point, I really have to rely on prime Kuma, at least he's not that much of a disappointment.