I am not sure what a DGS is? But it looks like you’re looking for a client-server solution for your card game.
I’ve posted this in other places as a suggestion, take a look at www.smartfoxserver.com. I think it is the kind of solution you might be interested in.
You can build the game logic on the server side and you get lots of useful features for match-making, managing rooms, users, chats, banning etc. The whole thing is free for 100CCU and pretty affordable if you want to scale up. For pricing check the elastic licenses, they are the most affordable.
Edit: also check these solutions