Were you ever able to find a solution to your problem? I'm experiencing the same thing running macOS 10.15.3. Upon initial connection with GlobalProtect I open terminal and run "scutil --dns". My nameservers show the IPs of the my internal corporate network. After a few seconds I can run the same command, and the nameservers has changed to localhost "127.0.0.1".
Click Accept as Solution to acknowledge that the answer to your question has been provided.
The button appears next to the replies on topics you’ve started. The member who gave the solution and all future visitors to this topic will appreciate it!
These simple actions take just seconds of your time, but go a long way in showing appreciation for community members and the Live Community as a whole!
The Live Community thanks you for your participation!