What is the right course of action here?

Your answer is correct because in Germany, overtaking near a rail crossing is generally prohibited or dangerous, especially when a slower vehicle like a moped is ahead. It is important not to overtake before the crossing to avoid risks from approaching trains and limited visibility. Patience and maintaining a safe distance behind the moped ensure you are prepared to stop safely if necessary. This rule helps prevent accidents at rail crossings where sudden stops or limited sight lines can make overtaking hazardous. Always wait until you are safely past the crossing and have clear visibility before considering overtaking.