08/2018 M3P. When this recall first went out I happened to be in for a tailgate issue (switch not responding), but was told they don't make this replacement unless there are issues.
Roughly a week or so ago, I started receiving the "black rear camera" issue, but it was intermittent. If the car sat, say overnight, and I got in it "might" work for the trip, but leaving on sentry and returning after leaving the car and it'd be gone. I submitted an initial mobile service, but then got pushed an update and right after the car applied it, the camera worked again so I cancelled the service. Later the same day, it was gone again so I rescheduled mobile service. For reference, I picked "Camera & Sensors" and stated rear camera was not working in car or via the app (sentry). When mobile service was approved, they had the "recall" on the list but I was originally quoted ~$90 for the basic troubleshooting, etc.
Service tech arrived, briefly checked the harness (nothing splayed on wires) and opted to replace it because camera wasn't working when they checked.
After he was complete, they 0'd out the cost as "Goodwill - Service". The only part was:
ASY,HARN,DECKLID,M3(1068789-00-G)
I do NOT have a plastic guide at that bend like some of the other photos here show. It's a new cable with what appears to be slightly more slack in that area.