Which low tier side character featured in an arc would have the most conqueror's haki?

[Warmmedown]

Koby
Rice ball girl (donut girl for Brock)
Dog in Buggy Arc
Gen with a pinwheel
Nojiko
Crocus
Old man in Java
Apis
Pell
Vivi's dad
Shirohoshi
Iceberg
Sea Train lady
Someone else

 

[Warmmedown]

Why is Iceberg so cool