If you haven't withdrew your RBTC yet, i would suggest you just convert it back to BTC to prevent similar problem later.
RBTC didn't have any trading pairs on Gate.io, that was part of the problem. Gate.io just lowered the withdrawal minimum and fees, but didn't add a trading pair.
I've withdrawn the RBTC and sent it to an exchange that does have such trading pairs (BitFinex). Now I can finally do business.
I was also surprised to read about rBTC on Gate.io, could that be an unofficial coin list on a big exchange like Gate. What is the possibility of withdrawing such a coin on the exchange without withdrawal details and private keys? What level of KYC is required to make withdrawal on Gate.io? what is the minimum value in BTC as well for withdrawal without KYC?