I visited the Terminal 3 Mena Lounge now which seems to also be branded with Plaza Premium. No issue accessing it with my American Express Platinum card
The lounge itself is barely better than the terminal. No windows and crowded make for a bad combination. On the plus side they had very nice bathrooms
Food was pretty limited: salad, sandwiches and chips and guacamole. Liquor selection was pretty mediocre. Service was good though, a waitress brought a refill to my seat which I appreciate.