This panel alone gives me the almost certainty that Zoro will be the one to take Kaidou's head. I mean, Oda could've placed that text bubble on anyone, but the fact that he placed it on Zoro of all people, and have Zoro almost replying to Yasue, after their connection? It's too much of a coincidence.
Also the fact that of all people in Punk Hazzard, Oda chose Zoro to behead the very first opponent that the SHs faced in the New World, which, coincidentally, was a "Dragon". Now i know people will say forshadowing means jack shit, but how many peope actually believed Kin will be able to split Boros Breath in 2, despite the fact that Oda literally forshadowed his abilities back in Punk Hazzard?