The main issue with an expert-only medal is that a lot of inexperienced players may flood the expert servers just for the special medal, no different than people flooding Gear Grinder because it gave the best loot for the least number of tickets. The idea of making expert count towards both medals is to make it optional for inexperienced players so they don't feel enticed to join a difficulty above their skill level to earn all the prizes.
That said, an expert-only medal isn't off the table, but we would need to come up with acceptable solutions to these challenges before we will attempt an expert-only medal.
That said, an expert-only medal isn't off the table, but we would need to come up with acceptable solutions to these challenges before we will attempt an expert-only medal.