You might also see if you still have access to your old Ripple addresses; signing a message with one of those would work equally well. Seems like you used this one a few times:
The question is, is it possible to sign a message from a ripple address, just like it is with bitcoin and Ethereum? I have done a quick search and there isn't much information, plus things look too complicated rGd4FaNjg22EvTuot3SRKF1suueUSc8Lhd
One thing that makes me wonder is who could just forget about their VIP donator account and just continue using a lower ranked account for all that long without appealing.