Going backwards didn't help as well. I went reverse but there was also another train behind.
Could you make screenshot of map with zoom? To see full situation with trains. Maybe you pushed the rail cars and they blocked the tracks ahead?
Unfortunately, I didn't record the game.
I passed this level once more time. All was ok. Try once more time please.
I didn't see anything ahead. If I touch the train at the junction, it could derail me. I didn't want to derail myself or else I would need to restart again during that time.
I'll try to do the mission again.