I had similar issues with a different VPN/Proxy at an earlier role. I solved with https://github.com/sakai135/wsl-vpnkit and trusting the root certificate of the proxy on the rancher desktop WSL2 vm (Assuming you're on Windows as I was).
Docker desktop pays for itself by solving these issues though IMO (I wasn't able to get a licence at the old role however)
Docker desktop pays for itself by solving these issues though IMO (I wasn't able to get a licence at the old role however)