Since there wasn't one out there already, I took a shot at it. It's really rough, and mostly cribs its implementation from the Postgres dialect (since Netezza is a postgresql derivative).
It handles a couple of quirks I ran across, like adding "distribute on" clauses to create table statements, and ensuring limit clauses don't get sql params (since it doesn't like that).
With pandas incorporating SQLA, I figure this might be useful to some people out there.
--Josh