Since Kassel-Würzburg is possible, Nürnberg-München could also be done, maybe also with an extra route that connects Nürnberg with Würzburg, Würzburg Hannover and Hannover-Hamburg so we could get all the routes we need for Hamburg-München
You forgot Nürnberg Augsburg line that is how the Nightjet reaches München Hbf from Nürnberg Würzburg and Asschaffenburg Hbf then Hauptstrecke München Augsburg. Missing link is the Nürnberg Würzburg line.
Good point and if made Schnellfahrstrecke Nürnberg München tutorials are in Training Centre for DB Baureihe 102 Skoda Dostos ICE 2 S-Bahn Nürnberg DB Baureihe 1440. However LZB Tutorial still Happens on the route. DLC Here ICE 3 Velaro D DB Baureihe 407/408. Layers Schnellfahrstrecke Hannover Kassel Würzburg ICE1 & ICE 3 Riesa-Dresden ICE-T and Schnellfahrstrecke Köln Aachen ICE 3M.