I'm not an aircraft engineer but have built quite a few other engines in my time, as an amateur. Isn't ring chatter caused by incorrect cylinder honing angle? The rings effectively "bounce" over the grooves left by the honing and don't bed in properly and don't scrape the oil as they should. This allows oil to reach the combustion chamber.
If your mechanic isn't honing the new cylinders correctly, changing them won't cure your problem.