Your lights do work... stand at the rear of your car, and lock your car (with your RKE) multiple times in a row, as fast as it will let you.. You will notice that each time your lights flash a LITTLE brighter..
I think the problem stems from insufficient voltage from the KEM to trigger the lights... after multiple times the lights have sufficiently "heated up" and are warm so they light more(???)
if you could have the light flash relay of the KEM trigger a relay that you added (this relay engaging the FULL 12V battery to your lights) they would be brighter, I would imagine..
Just a thought...
Ray