I think it depends on what "detraining after dark" means. If it means walking to her car in the parking lot, then no problem at all. There will be plenty of other people getting off the train and as long as the car is parked reasonably close, then she should be fine.
If "detraining after dark" involves waiting around for a ride, I'd be wary, especially on the final MARC arrival of the night, which happens after the station closes. Yes, it's a small town, but that means not a lot of activity nearby once other passengers have left. It's been a couple of years since I've used that station, but I don't recall any businesses open nearby that would be a safe place to wait. Most of the commercial activity in the area is several blocks away.