Hello,
No this will not work. First of all, these pre-built servers, such as the Small Green Computer and Wyred 4 Sound for that matter, usually come with a built in set of software packages. None of them are equipped to be able to control the software separately like you can with a computer. Also, these type of servers almost always run a version of Linux. Macintosh and Linux computers are capped at DSD128. They both use DoP as the transport to the DAC. DSD256 or DSD512 requires Native DSD drivers... which means they require a computer running Windows.
I use Windows 10 Professional on my server so that I can Remote Desktop which means I do not need a monitor, keyboard, and mouse attached. I also highly recommend 16 GB of RAM. To run HQ Player requires some real heavy duty computer power. I do not have CUDA processors running now. One of our son's has my video card but will be returning it shortly.
Oh, the servers you were mentioning do not have separate video cards, not expecting you to ever hook a monitor to them. CUDA Core is what is used on Nvidia graphic cards. Therefore one of those is required to use the CUDA capability. I have heard for them to really be able to help requires a powerful one, like a GTX1070 or higher. The one I am getting back is a GTX980. I will see if it helps.
Bottom line, if you seriously want to use HQ Player to up-sample to DSD512 you will need a powerful computer; a solid i7 CPU in a separate Windows box. 16 GB RAM or more, high end power supply, High level Nvidia graphics card, highly recommend SSD drives for internal storage. Roon works great as the controller and will also allow you to use your Tidal. And I would run Windows 10 Professional unless you are looking to have a monitor and keyboard, etc., attached to the computer.
Hopefully this makes sense...