You don't need to modify jsons. Install Nvidia driver which ships Vulkan 1.1.70.x. Also, install latest Vulkan SDK in the prefix. And can you also show how your registry key looks like?

my reg key :

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Wow6432Node\Khronos\Vulkan\Drivers]
"C:\\Windows\\winevulkan.json"=dword:00000000
and

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Khronos\Vulkan\Drivers]
"C:\\Windows\\winevulkan.json"=dword:00000000

I've just managed to get it to run with wine-staging 3.4 + dxvk HEAD, although the process is easy to mess up, so maybe it will be useful if I write what I did here.
To wit (I'm repeating official instructions, but maybe it'll be easier to understand when everything is in one place):

1. install wine 3.4; I used wine-staging, but I suppose either will do,
2. create a fresh wine prefix
WINEPREFIX=where/you/want/to/put/it wineboot
3. make sure it's Windows 10 with winecfg
WINEPREFIX=where/you/want/to/put/it winecfg
4. install vulkan SDK. If you have fresh winetricks (they added it this week or something) you can use it: WINEPREFIX=where/you/want/to/put/it winetricks vulkansdk
Otherwise download & install from https://www.lunarg.com/vulkan-sdk/
5. put winevulkan.json in
where/you/want/to/put/it/drive_c/windows
Contents of file are here – https://github.com/roderickc/wine-vulkan/blob/master/README.md
6. add Vulkan-related registry keys, as in the link above.
!IMPORTANT! if you add the keys with a reg file double-check the registry keys using regedit to see if the key names are okay; in my case it stripped the slashes making it not work at first. The key name should be exactly C:\Windows\winevulkan.json (with slashes); making sure this is okay will save you a lot frustration,
7. at this point you should be able to run
WINEPREFIX=where/you/want/to/put/it wine where/you/want/to/put/it/drive_c/VulkanSDK/YOUR_VERSION_HERE/Bin/cube.exe
and have it work; if it's not then either you messed one of the previous steps, or I forgot about something I did.
8. install https://github.com/doitsujin/dxvk (it's somewhat involved, because you have to first get MinGW64 working; lucky you if you have binaries),
9. do
WINEPREFIX=where/you/want/to/put/it bash setup_dxvk.sh
in the appropriate directory as per README (or globally, if your distro puts it into `PATH` like Arch package does)
10. enjoy this:


It works really well with dxvk, I had 5-15 FPS with vanilla on my GTX970; now I have 30-40, which is somewhat less than on Windows (by about 10-20 FPS IIRC, haven't played it in a while), but perfectly playable (if the figures seem low consider it's WQHD at Ultra bar anti-aliasing and hairworks). If you happen to have stuttering, try turning ambient occlusion of, it helped in my case.

Vulkan in wine setup script

I reinstall debian + Driver Nvidia depot + Winehq-devel 3.4 .
I test hispara script... same probleme
ERROR: [Loader Message] Code 0 : loaderGetDeviceRegistryFiles: failed to open DevNode ð
002a:fixme:setupapi:CM_Get_Device_ID_List_SizeW 0x22ed40 L"{4d36e968-e325-11ce-bfc1-08002be10318}" 0x00000300: stub
002a:fixme:setupapi:CM_Get_Device_ID_ListW L"{4d36e968-e325-11ce-bfc1-08002be10318}" 0x534a0 0 0x00000300: stub
002a:fixme:setupapi:CM_Locate_DevNodeW 0x22ed3c L"\02d0\0001" 0x00000000: stub
ERROR: [Loader Message] Code 0 : loaderGetDeviceRegistryFiles: failed to open DevNode ð
002a:fixme:setupapi:CM_Get_Device_ID_List_SizeW 0x22e920 L"{4d36e968-e325-11ce-bfc1-08002be10318}" 0x00000300: stub
002a:fixme:setupapi:CM_Get_Device_ID_ListW L"{4d36e968-e325-11ce-bfc1-08002be10318}" 0x6ce80 0 0x00000300: stub
002a:fixme:setupapi:CM_Locate_DevNodeW 0x22e91c L"\0110\0001" 0x00000000: stub
ERROR: [Loader Message] Code 0 : loaderGetDeviceRegistryFiles: failed to open DevNode 
002a:err:vulkan:wine_vk_init Failed to load Wine graphics driver supporting Vulkan.
ERROR: [Loader Message] Code 0 : Failed to open dynamic library "c:\windows\system32\winevulkan.dll" with error 1114
Cannot create Vulkan instance.
C:\VulkanSDKBuild\workspace\LoaderAndValidationLayers\demos\vulkaninfo.c:808: failed with VK_ERROR_INCOMPATIBLE_DRIVER
002a:fixme:console:GetConsoleProcessList (0x22f9e0,2): stub

Quoting: sebish[HKEY_LOCAL_MACHINE\Software\Khronos\Vulkan\Drivers]
"C:\\Windows\\winevulkan.json"=dword:00000000

This looks correct to me. Install latest vulkan SDK. Did you create json inside the prefix?

No , I download and copy in the wineprefix
#wget https://raw.githubusercontent.com/roderickc/wine-vulkan/master/winevulkan.json
#cp winevulkan.json ~/.local/share/wineprefix/Witcher/drive_c/windows

I have the same issue under ubuntu 17.10, I tried doing it manually and with an install script in another wineprefix, it always gives me that error.

My registry entries are correct, the json file is in the right place too, I have all vulkan libraries installed (linux and windows).

My graphic card is a GTX 770, driver 390.25 IIRC.

Could it be an issue with the lunarG library? I tried 1.1.71 and 1.0.68.

Quoting: jaen7. at this point you should be able to run
WINEPREFIX=where/you/want/to/put/it wine where/you/want/to/put/it/drive_c/VulkanSDK/YOUR_VERSION_HERE/Bin/cube.exe

If I launch cube.exe with double-click:


And via terminal:
bash: /home/dron/.wine/drive_c/VulkanSDK/1.0.68.0/Bin/cube.exe: can not run a binary file: Error in the format of the executable file

You can't run Windows binary like that from the terminal.