Steam Unable To Complete Cardiff City Network Journey Mode Due To Train Off Path Issue

2F50: Treherbert - Cardiff Central
Platform: Steam PC

Unable to complete the journey mode for this route as the signal before Cathays which I pass it at amber to stop at the station, the train always appears to be off path and will not go any further. I did submit a support ticket but didn't get anywhere. Has anyone finished this on the steam version and how did you get around this?