Fit File Repair Tool couldn't find any issues with your file and I was able to get exported version of it to upload to GC without any issues so FFRT may have subtlety fixed something.
*NOTE* I have also read that there are currently issues with uploading to GC due to a time zone change somewhere in the world affecting some of the Garmin GC servers. I may have just been lucky in getting your file to upload so I guess patience until the time zone issue is resolved is now needed.
