The spacing between the Drum Spacer (DDC) and Locking Pin (DEZ) is too large for them to mesh or engage (see pictures below). And If they ever did engage, I do not see said parts keeping the drum from rotating as the Drum Spacer and side panel plates (DCW) are not fastened together.

Also, step 2.5 of the instruction speaks to and depicts Leg Bracket (DDB) not overlapping with the Upper Leg (DCZ). This is not possible when nut (ADK) is tightened in step 2.11  as there is not enough surface area on Upper Leg to prevent this.