The Radeon Performance Overlay is working fine for me.
I have not tried it on Ark Survival Evoled though.
Perhaps there is a conflict between key bindings in the game and set in Adrenalin 2020 GUI/UI?
You can increase the sampling rate of the perfomance overlay from 2S to 0.2S in Settings -> General.
Maybe try Alt+z when the game is running so you get the sidebar to open first, then try the "Fullscreen" expand button at the top of the sidebar?
Or try Alt+z followed by Alt+r?
Thanks.