Seminarhaus Grainau is a 75 min drive from Munich/Garching and can also be reached by train to Garmisch and from there with the Zugspitzbahn (cogwheel train), with good connections from Munich. The Deutschlandticket (49 €-Ticket) covers the cogwheel-train connection Garmisch - Grainau.
You can find the timetable for the cogwheel train here: https://zugspitze.de/de/Service-Informationen/Betriebszeiten-Fahrplaene
Train info:
Munich to Grainau: Monday, 06.05.2024 10:32 (RB 6)
Leaving from: Munich Hbf., Gl. 31
– please be there at 10:15! Train will leave punctually at 10:32.