I mean, it could be a misspelling of "all correct," I guess, or "old kinderhook." No one really seems to know, but the fact that it doesn't matter says something about how we add meaning to words.
Creo que podría ser un error de "todo correcto" o "viejo gancho". Nadie parece saberlo, pero que en realidad no importa dice algo de cómo damos significado a las palabras.