I have similar problem with cemu, in my case testing 1.7.2b version with major vulkan improvements.
The vulkan driver 18.5.1 outdated makes visual glitches. I find this workaround with perfect results now.
 1-Download latest drivers
 2-Expand vulkan files, in my case: amdvlk32.dl_, amdvlk64.dl_, vulkan32.dl_, vulkan64.dl_, vulkaninfo32.ex_, vulkaninfo64.ex_ 
 3-Replacing files of system32 and syswow64. 
     3.1) amdvlk32.dll and amdvlk64.dll
     3.2) amd-vulkan32.json, amd-vulkan64.json
     3.3) renaming vulkan32.dll to vulkan-1.dll, vulkan64.dll to vulkan-1.dll, vulkaninfo64.exe vulkaninfo.exe
I don't know if this method is avaible with opengl...