Who was ordered to be in the right column? Left column? As looking at the German officer.

The personal perspective vs the external perspective

Explanation:

If you have two columns standing in front of a German officer, the people who make the colums will know whether they are on the right side or the left side column.

But the German officer will see the left column as standing to the right and vice versa. A logical error. I remember a famous female percussionplayer who told the story that she learned to play the congas (in front of her teacher) reversing the left hand with the right.