Hey i Found to very anoying Bugs in those Routes, on Clinchfield the service arround 5 O´Clock in the Evening gets stopped 16 Kilometers before the endpoint, because some Ai Shunting. But the Ai Train doesn´t move so you can´t complete it. Same on Dresden Riesa, If you drive a Freight Train to Dresden, 6:33 you´ll end up in front of a Train thats facing you. The Game want´s you to drive back 11 Kilometers which is not Possible because the rails are all locked up.
Is this the "Extra 3014" service? If so, you have plenty of company. We're all hoping this gets addressed at some point. IIRC, someone did manage to finish it by disregarding the speed limits, but that shouldn't be necessary.