Back then when you posted this, there is no Cryptocurrencies that are dedicated to gambling, but right now, there are coins like Eos and Tron that are dedicated to gambling, but it's better for gambling sites that they can and willing to accept as many coins as possible, to make their site competitive and popular among coin holders.
I believe these coins where already existing even as at when the post was posted. Tron coin isn't new and the post isn't an old post either. The poster wasn't aware and that is the reason for the post just like I was not aware of this also. I believe the aim of Tron coin has been achieved. It is indeed the most loved among other gambling site and almost every online gambler knows this.
I never believed in the possibility of having a coin dedicated to gambling, considering the volatility of cryptocurrency. I thought gamblers would be scared to use but it turns out that this is the best option to bettors and many see it as a good opportunity to grow their coins. No wonder, coins dedicated for gambling are growing by the day.