I doubt it is. Esp if it is not on all the lists floating around.
The RFC has their own discount plan -- the Safari Club.
That in another that maybe worth considering for you.
We joined years ago. It is one set fee, and that fee is not annual. It's a one time fee. And you will get the membership fee back in coupons.
Safari members get discounts on meals and merchandise purchase -- plus there are no waiting perks. (Front of the line -- which also can take awhile. But still a lot faster than giving a name and waiting with most guests.)
I think if members call for reservations over 24 hours in advance they have guaranteed time seating, instead of the front of the line seating.
I won't swear to all this in case conditions have changed since we joined. But it certainly may be worth your time looking into. The Safari Club is good at all RFC, and I think at their other restaurants.
I have only used our Safari membership as a walk up at RFCs.