In TS one can click on the Friends icon (bottom right of screen) and then on a friend's name to go to their station, then on their Museum icon to see what museum level they are at, which also shows how many of each train type they have collected. But, does anyone know how to inspect their Museum inventory to see which trains they are actually missing in order to dispatch them if you can? Can PF not program a useful function like this? I have sent them a ticket.
P.S. And more than a year later NOTHING has happened, despite PF's response that they appreciate player comments and will look into it ......