I would be very careful about that. When the timetable does not show a separate arrival time and departure time, then be very, very careful.....that means it only stays a minute or two!!
You would not dare want to stray from your car at such a stop except under the very explicit watchful eye of an attendant.
Plus, the time you spend locating each other, you could easily miss them anyway. They are not going to know where your car is on the train, you are not going to know exactly where they are standing, etc, etc.
No harm in them being there, to be sure, but do not expect much and be very, very careful.
The only places where the timetable shows a separate arrival time and departure time for your train are Harrisburg, Pittsburgh and Cleveland. Even at those stops, if the train arrives late, do not count on it to stay in the station the entire allotted time. Example, if a hypothetical stop is 20 minutes long and the train arrives late, perhaps it will get its business done quicker than usual and only stay about 15 minutes.