https://en.m.wikipedia.org/wiki/Lüttmoorsiel-Nordstrandischm... has a schematic of the track.

Looking at the map, it seems there are only two endpoints to the line on the island.

On the other hand, https://en.m.wikipedia.org/wiki/Nordstrandischmoor claims there are only 4 households on the island, so even assuming each has its separate fork, “each house” isn’t that much.

I wonder what system they have to prevent the two locomotives from meeting each other half-way through and to get one of the locomotives to a home when needed.