u/DraftQueasy4890

The cinematic and the hint definitely points to beating the train by hopping onto it, running along the roof to the end, opening the door, and traversing towards the front. This definitely seems like the "intended" way, and honestly feels the most thematically appropriate.

However, I didn't do that, and I'm not sure anyone would ever do that when just dropping down the side and doing it "reverse" seems so much easier.