John Laroquette was also on a short-lived show set in (if memory
serves) the St. Louis train terminal. It was a funny show and there were many interesting characters. What was the name of that show and whatever happened to it?

You're thinking of "The John Larroquette Show," a 1993 sitcom which lasted about three seaons.
I thought it was a great show, but the ratings were fairly low, and the downbeat premise of the series probably made NBC execs nervous.
The show changed timeslots a few times, and an attempt was made to lighten the tone of the show, but it was eventually cancelled in 1996.