Hi @Imabi 
I also just wanted to check and mention, that as you’re using WSL now, I’m wondering if the issue you’re experiencing with the NPM issue above might be related to the UNC path thing? 
- which you would need to map the WSL network path to an actual local drive in Windows first (if you haven’t done so?)
Could you please confirm if that Z:\ drive is the actual local drive you have in your Windows machine? or is that a mapped drive already (that’s mapping to your WSL network path: \\wsl.localhost\docker-desktop-data\ ?)
In case you haven’t mapped the local drive to that WSL network path, perhaps you may want to try to perform this command line (in Command prompt) something like this:
net use x: \\wsl.localhost\docker-desktop-data
(note: where x: can be changed with any local drive you would want to map/assign for that WSL network path - as long as that “x” drive does not exist on your local computer) - similar to the one I mentioned in the other thread here and here .
Once done, you can go to that x: drive via command prompt , and there CD to that folder:
data\docker\volumes\DevKinsta\public\spiegelando
and see if you can perform that npm command line? 
Best regards,
Agus Utomo