Please post the output of mhwd -li
If mhwd can't detect drivers try looking at this thread: Nvidia Drivers Installed but mhwd doesn't show them - #3 by WernerRomling
I use optimus-manager with nvidia drivers too. Maybe you can try installing optimus-manager-qt to switch drivers easily.
I use the nvidia-all drivers. You can try using these drivers.
Make sure you are installing the dkms version AND the headers for the kernel you are using, (probably linux-zen) or else custom kernels like the one garuda is using won't work.