I found the route to the link for the many people who are having this problem.
From My WikiTree, choose Contributions.
Within the list of contributions you will find:
You Uploaded xxx for GEDCompare
Click on the .ged file link
Within #2 you will find the link:
GEDCompare Report: Complete
Your GEDCompare report is ready. Please click here to review it.
Very long winded and very well hidden but there it is!
I'd like to suggest to the developers that GEDCompare is a link in the WikiTree Dropdown list so we can all find it!