Private Instance - Chrome - URL not loading when triggered with proxy

[jfowler]

What was the exact resolution to get this working?

When I use the Chrome command line from the web under Advanced Settings:
--proxy-pac-url=file:///C:/webpagetest/config.pac

This works as expected. Any attempt to add this to the wptdriver.ini does not work. Oddly it opens a number of tabs where it appears to be getting script commands. However, the commands are getting treated as URLs.

wptdriver.ini
command-line='--proxy-pac-url="file:///C:/webpagetest/config.pac"'

My goal is to have this as default and not have to enter it for each test through the web ui.