Tranny Pan Gasket and Leak

Have a huge leak from my brand new tranny pan gasket. My local, old time Mopar mechanic says that if the pan is completely flat around the mating edge, I can use any gasket, but if there are raised parts I must use a cork gasket. Problem is, I get the pan off and the mating surface is flat with INDENTATIONS, not raised edges. Did I hear the guy wrong? When his shop opens tomorrow morning, I'll run the pan over and ask him, but in the meantime, what do you guys say? 69 Polara with a 383 and Torqueflight tranny.
Author: 69 Polara