AICC Content Won't Track or Resume in a Cross-Domain Environment

I have a specific question related to the fix identified in this thread; https://www.articulate.com/support/storyline-2/aicc-content-wont-track-or-resume-in-a-cross-domain-environment-463

The fix states in steps 4 and 5 the following;

4. Open the course.au file in a text editor, such as Notepad.
5. Update the URL to point to relay.asp file where it'll reside on your content server and save the change.

My question: Which field in the course.au file is the URL?

My course.au file is structured as follows;

"System_ID","type","file_name","command_line","Max_Time_Allowed","time_limit_action","Max_Score","Core_Vendor","System_Vendor","Mastery_Score","Web_Launch","AU_Password"
"A001","story","index_lms.html","","9999:59:59","C,N","","","Articulate Storyline 2","","",""