You are taking a rather large chance sending bitcoin directly from Gemini to a mixing service. Coinbase closes accounts for that. FWIW at least use an intermediary wallet.
Really? That's not good news. I asked a friend before doing this and he said that he sends to helix straight from Coinbase and has for over a year and has had no problems.
Yeah, thats one of the many horror stories when it comes to using Coinbase and Coinbase only, I've had friends who were buying BTC in order to gamble with Bitcoin who got his account frozen for months on end with tens of thousands of dollars in their. This is why I would recommend using another wallet in between such as Blockchain.info, BitGo, or so on.
I'd rather spend the extra transaction fees than have my money locked up, but I guess that's me.