Yes, it is free if you're flying TG in Business or First Class. I just flew TG yesterday in business class and got into the lounge with just my boarding pass and without ever showing my ROP card which is still only silver (but very soon to be gold). Depending on what time you get to the lounge though, seating may be quite difficult as right now many other lounges are not yet open. If you're flying a different airline other than TG, then you'll need to check with your airline if they allow you to use the TG lounge, some other lounge, or no lounge.