Cate's RX

Just had my '08 RX350 in for service and asked them to check the driver's side headlight that just went out a few days ago (obviously due to the condensation that just started after a huge rain not long ago). My service rep just called letting me know it would be $2557 to replace the headlight assembly! He said that "warranty enhancement program" ended in October 2015 and the previous owner would have gotten the notice. But I'm reading that unless the assembly had failed, Lexus was not just replacing the headlamps completely anyway. Now they're saying that they will not replace this. Is there another step I can take to make them replace this obviously defective $2500 headlamp? This is my third Lexus and I've never had trouble like this with Lexus. Very frustrated!!!