There is a "passenger information system" at all stations, it says "RE to (City), departure at (Time) on track (Track). And if that breaks, you can ask the Train Driver or other passengers.
Ok this may be another solution obviously. But as far as the game is concerned there seems to be no alternative but to leave the destination announcement empty.
You could call that a "Störung" at the destinationsdisplay Happens too often, else, passangers could know it from the stations informationsystem
Oh yes this can be considered a display failure. LOL. But I'm thinking of an oversight on the part of DTG in this road