Some games are more critical than others.
For example, if the Cards go 2-2 and the Rams go 3-1, we lose most scenarios. However, based on common games played between the team, if the Rams' one loss is to the Ravens, and the Cards lose to the Seahawks and one other team other than the Cowboys, we overtake them.
The Cards' loss to the Seahawks creates a tie in the divisional tie-breaker (4-2).
The Rams' one loss to the Ravens puts them at 9-4 in common games played.
The Cards' losses to the Seahawks and (one of the Lions or Colts) puts them at 9-4 in common games played. This creates another tie at this level.
However the Rams would be 9-3 in the conference, while the Cards would be 8-4 (if they lost to the Colts), or 7-5 (if they lost to the Lions).
IOW, we need to either win 2 more games than the Cards or hope for the combo above.