I Don't know that I believe that. The brakes release just fine, but the marker never appeared. And I can't contact the dispatcher.
I know it's not ideal but exiting and then starting the service from scratch is your best bet. Services usually play up if you save mid game. I had a similar sort of issue with Cumberland Charge, at the very end the signal wouldn't go green so I had to restart. It was probably due to me saving the game earlier on.
I did this two times and in both cases, I got the marker after 10 minutes. Therefore I feel confident in saying that this is the solution to your problem.