Oxygen installation issue solved.
Found the Oxygen installation location using the “Site path” in the Settings folder in Kinsta. Then I navigated to the folder in my Mac and deleted the entire Oxygen folder. Reinstalled Oxygen using the WordPress plugin installer. Oxygen 3.8.1 is running at this point. I am happy as a clam at high tide, so far. 
Hope this helps the next person who may encounter this error.