It's unlikely that Kaido will even die in the first place seeing as it's what he wants.
It's even less likely, though, that somebody like Zolo would be the one to do it compared to Luffy.
What matters here is intention. Anyone can look at the reasoning Zolo has for wanting to kill/defeat Kaido compared to Luffy to realize how shallow, and really quite undeserving, they are.
Zolo's intent, first and foremost, are HIS OWN personal satisfaction, HIS OWN meaningless vainglory and to satisfy HIS OWN personal bloodlust. Sure, he may also want to do so for Hiyori, but we can see based on his statement to Queen remarking Kaido as "THE STRONGEST" that he is primarily doing it for his own selfish intent just like every major fight Zolo has gotten in.
Luffy's intent, on the other hand, first and foremost is a much more selfless, retributive and constructive basis that is rooted not in his own, but for the people of Wano and all others who were indirectly harmed by Kaido's misdeeds. Unlike Zolo, who seeks only to fufill his own temporary and ultimately worthless dream of vainglory, Luffy wants to bring liberate an entire country and deliver redemption on behalf on decades worth of suffrage for millions of people.
It's for the same reasons Oda had Luffy defeat Doflamingo rather than Law. Sure, anyone would agree that Law has more personal reasoning and justification for defeating Doflamingo, however, Law's reasoning focused only on himself and his relationship with Doflamingo, caring not for all those millions who suffered along with him. His reasoning is rooted in hatred, wanting to see destruction as it's end. Luffy on the other hand had an intention laden in compassion and love, caring for Doflamingo's destruction only as a means to bring construction to all of Dressrosa.
All in all, someone like Zolo does not deserve to kill/defeat Kaido because his intentions are not coming from a place of charity and compassion, but of hatred and bloodlust.