Hello Tristar1011
Yes, with your gold card you can check in at the F counter, and there should be no problem about your parents doing the same with you, especially if you are on the same booking. And yes, they will tell you that you allowed one guest only. You will of course all be able to use the very nice south Galleries Club lounge. Many if not most will consider it inappropriate to bring one guest into the F lounge and a while later bring another guest in.....