I don't see an option to disable Certificate Pinning on MAC version of Enpass, but I accidently discovered a solution at least for Zscaler. When you disconnect and reconnect to the network (wifi), it takes a few seconds for Zscaler to start redirecting traffic. If you try to register within these first few seconds - it goes through. Then when you receive a pin, you have to disconnect and reconnects network again and quickly put the pin in. I got it to work this way. YMMV. Good luck!