Yep, it does show up in Server 2019. Pic: https://i.imgur.com/bib4kI7.png
Yeah I am all too aware of this issue as an AMD user (both CPU and GPU). Using an R9 Fury – everything was detected fine on an older driver, but now it refuses to install automatically.
Thankfully I have found a solution that allows you to both install the newest drivers and the radeon control panel. Let the installer extract the files to C:\AMD. After that, you can install the driver manually by finding the .ini file, right clicking and installing it. After that you should be able to use device manager to update normally. To install the control panel/relive, you have to manually run an exe in the folder, though I don’t remember the exact path.
I could elaborate more on this process later (already have everything installed), but for now hopefully that helps you.