Final answer:
The SS officer who beat Elie's father for not marching in step to coax Elie into surrendering his gold crown in the memoir 'Night' is Franek, the foreman.
Step-by-step explanation:
The question relates to an event in the memoir 'Night' by Elie Wiesel where an SS officer beat Elie's father. It is a historical moment within a literary work, representing the horrors experienced during the Holocaust by Elie and his father in a Nazi concentration camp. The specific SS officer is not named in your provided passages, but in the book 'Night', it was Franek, the foreman, who noticed Elie's gold tooth and wanted it. He beat Elie's father for not marching in step to coerce Elie into giving up his gold crown.