How is that your interpretation man?
Garp was there because of Koby.
Garp was only captured because of Kuzan.
It's incredibly forced. Sanji has more ground to fight against a corrupt king from North Blue but you won't even bat an eye at those parallels.
I do sure hope "The Hero" Garp's apprentice, "Hero Koby", doesn't fight Garp's other apprentice who conveniently defeated and captured Garp.
That sure would be an unexpected, left field plot point.