From your scenario, there will be 4 or 5 approvers in each sequence. If they are all individuals and not in the same group, the current design cannot meet your requirement. So could you try to make the definition like this?
1. To make those 4 or 5 approvers in a group. And then define the approval definition against the group for each sequence. It means the approval definition for each sequence is defined against different groups
2. Approval type: All must approve - immediate denial